June 24 Colombo - Male - Vilu Reef
After an impressive week we slept again at the Browns Beach hotel in Negombo for a stop on the way to the Maldives. The previous day we arrived around 18.30 PM and this night we were waked at 3.30 AM because we had to be at the airport at 4.45. When we arrived around 5.30 there all luggage had to be checked twice through an x-ray machine and one time inspection by hand. After a huge row before the desk where you have to pay airport tax (thanks to Globe for not pointing this out before on the travel documents) and another line before customs we passed everything around 5.45.
From Sri Lanka you fly in about 70 minutes to Male, the capital of the Maldives. This country only exists from islands and the whole territory is about 820 by 120 kilometers. It's located in the Indian Ocean near India and Sri Lanka. The Malidives were occupied by the Portugese for a short term and by the English but most of the time they were and are independent. Also the islands played a role as a stop to and from Asia. About 200 of the 1200 islands are inhabited by about 260.000 people and about 90 islands are exclusively reserved for tourism. Tourism makes about 25% of the economy. The existence of the Malidives is threatened by the rise of the sea level and if the predications become the truth the country will vanish into the sea.
When we arrived all luggage had to be scanned again because customs was looking for religious statues and of course porn and drugs. Our fellow travellers also went to the Malidives and they bought two large buddha statues on Sri Lanka and those were detected. This meant that they had to leave them in the luggage depot on the airport and could collect them on the way back. I only bought a small hindu statue and that wasn't found. Outside the terminal there are several counters from all local travelagents and we missed ours. He was paying attention and found us at the airport so that was not a problem and very helpful from his side. Scary was that he insisted on having our tickets in order for him to confirm them and keeping them until our return flight. This wasn't announced by Globas and I still feel this is not the way to handle your tickets by not keeping them yourself.
From the airport we went with a small bus to the other side of the airport / island, because there was nothing more than the airport on this island. Male the capital is on the neigbouring island. Around 9.10 AM local time we left with a waterplane. This was really an interesting experience. Pilots in bermuda without shoes flying their plane, a cabine with just 12 chairs, a short runway on the water and when the plane went through the clouds small drops of humidity came along the windows on the inside. The landing was about 40 minutes later and was a few 100 meters from the island next to a small pontoon. A boat was waiting for us to bring us to the island.
Vilu Reef is part of the Dhaalu atol also called the South-Nilandhoo atol. On the island there is only the resort so you'll find only bungalows and provisions for tourists. They have around 80 bungalows on the island. The island is about 300 meters in length and 150 meter of width (this is a perosnal estimation).
We could immediately occupy our bungalow. It as a magnificent bungalow, very close to the beach (20 meters), nice big bed, excellent air-conditioning and also a fan. Together with the bungalow you get your own servant who is reponsible for your bungalow and all corresponding things to it. The same afternoon we had our first tropical rain but fortunately it rained immense but for a short time and this was the only rain we had during the trip.
At night we went to diner in 1 of the 2 common provisions on the island namely the bar and the restaurant. Food was excellent and was by buffet. We booked half-board so at lunch we could decide what we liked to do at that moment and big advantage is that you will not gain that much weight. At dinner you have your own servant that pours your glasses the whole week and cleans your table. These guys (no female to be seen except western foreigners because of their language capabilities) come from another island and work about 2 months before they are off for a week or 10 days.
June 25
Fantastic weather. Ofcourse we went to the beach. The same day I was sunburned already. Around the island there is a reef such that you have a part to the reef for about 30 meters that goes to a depth of 1.3 meter, then the rocks and coral of the reef and next the bottom of the ocean is going down very steep. The same day we saw a group of little sharks swimming inside the reef and outside a groupm of dolphins were passing. As you can see on the picture below the water was very clear and it is indeed very beautiful like the brochures indicate.
June 26
In the morning it was cloudy so an excellent day for snorkeling. On the island there was a diving centre where you can hire a pair of snorkels and webs for 5$ per day. We went snorkeling three times that day and saw beautiful fish that swim mainly on the outside of the reef and very close to the reef. On the outside of the reef we noticed a pipe going into the reef. Its purpose was not clear.
When we went snorkeling I remebered a previous experience and we put on a t-shirt. We were glad we did so because around the shirts we were burned again by the sun. Amusing was that we saw a group of German pass us on the beach who went snorkeling in bathing suits. The second time they went snorkeling they wear shirts and the thirth time they even had put on trousers.
In the mean tiem it was clear that the prices in the bar were quite expensive, such as 2,5$ for a soda and 3,5$ for half a liter of beer and very strange also 3,5$ for a liter of water. We then had the prices of Sri Lanka in our head as I read my notes now because a few months I'm used again to Dutch prices and then those prices were reasonable if you note that everything is delivered by boat or plane. I was glad that there was happy hour and that was the time to try some cocktails. For 5.5$, which is as much as you will pay here, you get quite a nice cocktail and that is and should be part of this surrounding.
The diner was great that night also because of a special dish with all kinds of fish. Ofcourse fish was on the menu regularly because you're in the middle of a sea surrounding you. Because of the proximity to India they regularly have different kinds of curry dishes. Unfortunately my stomach problems were still there and each time I ate something spicy my stomach was reporting new problems.
June 27
Before we were returning the snorkeling stuff, we sparing Dutch men we went snorkeling at 9.00 AM for half an hour. Because it was still very quiet we saw lot's of fish. The weather was great again that day such that I burned again. It was starting to hurt me now. I was almost in the middle of my remaing book so I slowed down reading because I forgot two books to bring with me. That day we ate some Dutch waffels with syrup that we found by accident in our luggage but that didn't matter because they were delicious.
June 28
I woke up with a headache feeling, was it the cocktails or was it dehydration? I finally took some pictures. There was not much to do and see so I didn't have the urge to take a lot of pictures. after all we still had some days left and time enough to take pictures. This day wasn't spectacular because it was partly cloudy and we filled the day with sleeping and eeting.
June 29
This is the day when we starting to get bored. Again partly cloudy and this time a nice wind. I keep on using suncream factor 12 but I seem to be past the stadium of getting burned by the sun. Louise is already trying to use oil instead of cream. To her own suprise she's getting bored of the sun as well.
Today I finished my book. Fortunately there is a small library on the island. It isn't much, mostly books in English and German but also Japanese which I can't read. I found a book with several small detective-stories and started on that one. Besides that I read all the magazines Louise brought with her so my knowledge about modern women hypes and pregnancies were updated.
We thought about doing excursions but a boat trip for 25$ per person to the neighboring island is nothing more than a way to spend your time and money. Diving was not an option because Louise isn't allowed to dive because of her eardrums. When we returned from diner the whole bed was decorated with leaves of flowers which was very romantic.
June 30
Another beautiful day. We had rain for about 5 minutes but then the sky cleared immediately and before you realize it it just line it never rained. We were invited for dinner at the beach that night. This is done especially for honeymooners. Your table is decorated in a special and beautiful way but you can get your own dinner from the buffet because you dine right in front of the restaurant on the beach.
July 1
After rain you always get sunshine at the Maldives. That night the weather was quite rough and the next day it was beautiful again and quite hot again. Despite all previous sessions in the sun we burned again. In the afternoon I went to watch Formula 1 in the bar where they have a sattelite receiver. That day also our flight time was announced for the next day. It turned out to be 16.45 PM. We were glad because of our departure time at Male was late and because of this our last day was almost a complete one. Next problem was determining the height of the tips. The bar was a problem because several people helped us and all tipping them nicely was too much for us.
July 2
Our last night was not the best. Because of the bed that was too short and very hard, the noice of the fan or the airco I had troubles sleeping. In the morning we went to the beach for the last time and could stay until around 12.00. We then went to pay the bill which was like we expected but there was made a small mistake in calculating the prices of the cocktails for 10% discount during happy hour instead of 20%. The mistake was immedaitely corrected so that wasn't a problem at all. We solved the tipping problem by giving the guys for taking care of us the most a tip, so the room boy, restaurant guy and our favourite waiter in the bar.
At 17.00 the plane finally arrived so we had plenty of time. On the other hand the plan couldn't be much later because these waterplanes are not allowed to fly at night and around 18.00 P.M. it gets dark pretty quick. A fellow passenger had a television as luggage and he had to leave it behind because of weight restrictions. The waterplanes are due to a strict maximum weight limit. We first had to make a stop at another islandand around 17.00 P.M. again we arrived at Male. Male is on an hour time difference with Vilu Reef.
Our travelagent was already waiting for us with the tickets which he already confirmed for us. It was nice he did this already because it is necesaary to confirm your flight and phoning is very expensive at the island. He also knew somebody who could bring us to Male and show us something of the town. We left our luggage at the depot at the airport for 3$ per piece. At 18.30 we already finished the tour because it's very small. In a square kilometer you'll find almost everything. We ended ofcourse in a shop, this time the "uncle" of the guide". Uncle gave it a lot of trouble in selling something to us so we gave in and bought something. Also in these places you can try to bargain, we bought a t-shirt and a picture frame for 21$ and if I remember correctly he started around 26$.
We walked a bit by ourselves but stopped that quite fast because of the heat and most shops were closed because of evening prayers. The guide showed us restaurant Seagull and promised to meet us there again. He also wanted to go the parayers at the mosque. We ate somethin there and it was quite good. Strange thing was that the menu showed all prices in local curreny, rufiya and when we asked the bill and the exchange rate it turned out that it they only accepted dollars. We didn't have any local currency but the total amount wasn't that much in dollars so we payed without making any problem.
The guide brought us to the harbor to a boat to bring us back to the airport and there we retuned around 21.30 P.M. In the beginning he already indicated that we shoud decide for ourselves what we wanted to tip him. I gave him 5$ which I thought was quite enough for about one hour work. It looked like he wasn't disappointed.
At the airport we had to wait for the travelagent again. Why wasn't clear because we had our tickets already and just said he would meet us at 23.00 P.M. In the mean time we solved the riddle of the Coca Cola. This doesn't taste at all at the Maldives and think this is the same taste as they tried to change Coca Cola in about 10 to 15 years ago and which was redone after lots of protest. Buying something at the airport is also quite expensive because you'll pay 3$ for a Fanta for example. Changing money at the airport is impossible because there is no bank so I couldn't figure out the exchange rate there as well. You can pay everything with dollars or credit card. In the mean time I found at the internet that you get about 12 RF for 1$.
At 23.15 the agent was still not there and another agent approached us and asked if he could help us. We then entered the hall for checkin with help of this agent who showed us the way and helped with the luggae. His help was a bit strange because everything is indicated very clearly but he probably wanted to be just friendly. He didn't ask or indicate anything about a tip so not everything is suspicious. Generally my impression is that the people of the Malidives are very friendly and helpful..
At 1.30 our plane left and around 2.30 we landed on Colombo again. The next flight was at 4.30 AM for London but unfortunately we departed an hour later. We spent the time in the bar at the airport where we met a couple from England and time past quickly due to the conversation we had. The return trip was long and boring and fortunately we were on time for our connecting flight to the Netherlands. We arrived around 18.00 P.M. at home which brought our return time to 24 hours.
The end
The Maldives are a wonderful country and Vilu Reef is a beautiful island. Only if you don't bring several books and you're not going to diver you'll find about 5 days for a stay enough. Assume it's expensive and do count on it so you don't have to take care of your budget when you're there. It was absolutely worth the trip. The combination with Sri Lanka is fantastic and I can recommend it. One tip try to get a direct flight to the Maldives and possibly go from there to Sri Lanka or the other way around because when you also have to change planes like we did in London it makes it a very long trip.
Tuesday, September 21, 2004
Sri lanka Fishing
For several decades, a great deal of government money and foreign aid has been directed towards expanding and modernizing Sri Lanka's fishing industry. The nation's citizens have been encouraged to eat more fish and Sri Lankan fishermen have been heavily subsidized in an effort to satisfy the consequent growth in demand for fish and fish products.
The direct result of the expansion of these fisheries has been the death of tens of thousands of small cetaceans in Sri Lankan waters. Many of these are entangled accidentally in coastal gill nets set to catch fish such as tuna and sharks, and others are taken by a large-scale commercial fishery which kills dolphins deliberately for use as bait.
In the past, dolphins were sometime accidentally entangled in fishing nets in Sri Lanka's coastal waters. However, the nets were made of natural fibre such as jute and cotton and the dolphins could either detect them with their sonar or break free if they did become entangled.
Then, as part of an extensive programme funded by the UN Food and Agriculture Organization (FAO), designed to encourage the modernization of Sri Lanka's fisheries, nets were supplied that are made of stronger materials, which the dolphins can neither detect nor break. These gill nets are now being used, in some areas, to catch dolphins deliberately and a market for cetacean meat, which did not exist prior to the FAO net programme, has now developed.
Conservationists are concerned that the total catch may be extremely high. Interviews with fishermen from Tangalle, in the south of the island, suggest that they generally take 10-25 dolphins a day in gill nets between March and July each year; if true, this would amount to an annual icidental kill of between 1,800 and 4,500 dolphins by fishermen from this one town alone.
A report written by marine mammal scientists Stephen Leatherwood and Randall R. Reeves (based on studies by Abigail Alling in conjunction with the Sri Lankan National Aquatic Research Agency [NARA]), was published in 1990 by the United Nations Environment Programme (UNEP). This estimated that between 25,000 and 45,000 small cetaceans may be brought ashore every year having been killed, deliberately or accidentally, in Sri Lankan waters. It isn't known how many dolphins are killed and used as bait at sea, although NARA had previously estimated that bait fisheries were responsible for 25 per cent of the total dolphin kill in the area.
Tragically, the size of this catch is likely to increase as the market for dolphin meat grows and the commercial fisheries in the region continue to expand, creating an increased demand for bait. At the same time, dolphins are being killed by harpoons fired from 3.5-tonne ships in some areas when catches of the usual target fish are poor. With the decline of fish stocks, particularly tuna, the number of dolphins being taken is likely to grow.
The Sri Lankan fishery is a case study in how well-intentioned programmes can have unforeseen and damaging effects. It is a difficult situation to tackle, given the enormous financial incentives for fishermen to modernize and eexpand their operations. Any efforts to conserve marine mammals, or for that matter fish stocks, in Sri Lankan waters will understandably meet with strong local opposition. Consideration has to be paid to the interests of those may Sri Lankans for whom the sea's resources may provide their best, if not their only, means of securing a better standard of living. A programme, jointly sponsored by UNEP and NARA, is currently working to educate fishing communities about the problems of over-exploitation.
Effective regulations of fishing gear, seasons and areas could enable fisheries and dolphins to co-exist in Sri Lankan waters. However, fishermen, scientists and environmentalists must strengthen their co-operative efforts to ensure that these regulations are developed and implmented in the interests of all.
RISSO'S DOLPHIN (Grampus griseus) - AMERICAN CETACEAN SOCIETY FACT SHEET
Class:Mammalia
Order:Cetacea
Suborder:Odontoceti
Family:Delphinidae
Genus:Grampus
Species:Grampus griseus
Risso's dolphins, also known as Grampus, are one of the larger members of the dolphin family. They are usually an offshore dolphin whose inshore appearance is uncommon. In numerous instances though, groups have moved into inshore areas where they have been seen repeatedly over a fixed period of time. Despite this, they are seen with some regularity in Monterey Bay, California, and off British Columbia. They have distinctive body markings and they have only 7 or fewer pairs of teeth in the front of the lower jaw, and typically none in the upper jaw.
PHYSICAL DESCRIPTION This is a relatively robust dolphin with a rounded head, similar in shape to the more familiar pilot whale. They have an unusual external vertical crease in the melon (the organ in the rounded head used to direct sonar clicks) that runs from the front of the forehead to the mouth.
COLOR Adult Risso's dolphins are usually dark gray with extensive white scarring. The scars can be scratches, splotches, or circular marks and, in some animals, can be so extensive that the entire body appears to be white. This scarring may come from bites from other Risso's dolphins, squid bites, or parasites. As calves, their bodies are a uniform light gray, which then darkens to a brownish-gray in juveniles. Risso's dolphins also have a white anchor-shaped patch, similar to pilot whales, on their ventral/chest area (from throat to stomach).
FINS AND FLUKES The dorsal fin is tall, falcate (curved) and located near the middle of the back. The flukes are broad and curved with a deep median notch. The flippers are relatively long and thin, and pointed straight back. The tailstock, or peduncle, is very slender.
LENGTH AND WEIGHT Length is typically 10 feet (3 m), although animals have been recorded up to 12.5 feet (3.8 m). Like most dolphins, males are typically slightly larger than females. Weight averages about 650 pounds (300 kg), and large individuals may weigh up to 1100 pounds (500 kg).
FEEDING Reflecting the offshore distribution of this species, primary prey appears to be squid, although they have also been known to feed on a number of fish species. While the size of their squid prey is unknown, squid beaks from species that grow up to 12 feet in length have been found in the stomachs of stranded Risso's dolphins.
MATING AND BREEDING While the age at which these animals reach sexual maturity is not known, it appears to occur when the dolphins are approximately 8.5 to 9.2 feet in length (2.6-2.8 m) in both sexes, and probably less than 13 years of age. Little is known about calving and breeding, but evidence from the North Atlantic Ocean indicates a summer calving season. Estimated gestation is 13-14 months. Calves are generally 4 to 5 feet long (1.2 - 1.5 m) at birth.
DISTRIBUTION AND MIGRATION Risso's dolphins tend to prefer offshore habitats worldwide in the warm temperate and tropical waters of both hemispheres. They are not known to enter true polar waters, and northern-most records are Newfoundland and the Shetlands (Atlantic), and the Gulf of Alaska (Pacific), while southern ranges are Cape Horn, the Cape of Good Hope, Australia and New Zealand. General migrations are not known, although some individuals may shift to cooler waters during the more productive summer season. Regional variation in movement may be related to local environmental changes, especially warm water occurrence, and shift in prey abundance.
BEHAVIOR AND NATURAL HISTORY Typical groups of Risso's dolphins are 3-30 animals, although "super-pods" of up to several thousand together have been noted. However, recent studies indicate that groups may be stable, and may consist of related individuals (especially females), although this has yet to be confirmed. They typically travel side by side, and are fairly active. Observations of leaping, spy hopping, fluke slapping, and flipper slapping are common. They are long-lived animals that live an estimated twenty years minimum and possibly up to twice that long. Risso's dolphins also form traveling pods at sea with other dolphin species, and hybrids between Risso's dolphins and bottlenose dolphins have been recorded both in captivity and in the wild.
POPULATION STATUS While formerly thought to be rare, this impression probably resulted from the typically offshore distribution. In fact, the species is probably abundant throughout its range, although no exact numbers are known. 13,000 - 30,000 animals are estimated to occur off of central and northern California. In a few parts of the world, Risso's dolphins are killed for human consumption. They are commonly found in the open market in Taiwan, and they are part of the Japanese drive fishery for dolphins. In Sri Lanka, they are one of the primary species taken in a gill net and harpoon fishery that may have grown out of selling accidentally netted dolphins. In most areas of the world, however, they are not currently under major threat from direct killing, but may be susceptible to accidental fishing gear entanglement and pollution from coastal development.
Bibliography
Ellis, R. 1982. Dolphins and Porpoises. New York: Alfred A. Knopf Books.
Kilowska, M. 1991. Dolphins, Porpoises, and Whales of the World: The IUCN Red Data Book. UNEP publications, International Union on the Conservation of Nature.
Leatherwood, S. and R.R. Reeves. 1983. The Sierra Club Handbook of Whales and Dolphins. Sierra Club Books.
Martin, T. (ed.). 1990. The Illustrated Encyclopedia of Whales and Dolphins. Portland House Books.
Wursin, B., T.A. Jefferson, and D.J. Schmidley. 2000. The Marine Mammals of the Gulf of Mexico. Texas A&M Press.
Dolphins & Whales
There are over 70 species of whales, dolphins and porpoises known to exist today. All whales, dolphins and porpoises are mammals. This means they share characteristics which are found in terrestrial (land) based mammals. For example, they are warm-blooded, they breathe air and give birth to live young. These young are suckled on milk secreted by mammary glands of the mother. (They share the classification of mammal with humans, dogs, elephants, for example.)
Toothed whales comprise a large group of the cetaceans, including dolphins, porpoises and the whales with teeth. They demonstrate an incredible range of forms, behavior and lifestyles that reflect their evolutionary history and the variety of environments in which the live.
Many, if not all, toothed whales have the ability to locate their prey using "echolocation". Echolocation clicks, similar to sonar, are intense, short pulses of amplitude-modulated sound. These pulses sound like a series of clicks (similar to a rusty hinge on an opening door) and are produced in the melon, or forehead, of dolphins. Dolphins direct these clicks at objects in their environment: the returning "echoes" are reflections of the emitted clicks after bouncing off the objects.
Many of the toothed whales also produce frequency-modulated pure-tone sounds, e.g., whistles. These sounds are probably function primarily in the exchange of information among individuals. Communication is an important aspect of any society or collection of individuals. Dolphins and whales communicate with the variety of sounds they produce as well as with body posture, movement, and physical contact behavior.
Communication
Dolphins are thought to be highly intelligent creatures due to their relatively large brain size and apparently complex communication systems. Such conclusions, however, remain the subject of debate. These animals must not be measured according to how close they come to equaling human intelligence and development, but rather accepted and appreciated for what they are.
Body Contact
Dolphins have a well-developed tactile sense. They are often in contact with traveling companions. Body contact is an important component in communication, and is accomplished through rubbing, petting, and hitting among other forms of touch. Some examples include the contact between a mother/calf pair, pectoral fin to pectoral fin rubbing, swimming while remaining in contact with another, and rubbing bodies. Mutual pectoral fin rubs may be exchanged by two dolphins that have just come together. These may be a sort of greeting, similar to a handshake or hug between two people. Or, sometimes dolphins swim a distance and one individual rests its pectoral fin along the side of a second individual. This behavior, called contact position, may be a signal to others that these two are close friends. It could also mean that the first dolphin wants a favor, so to speak, from the second.
Body contact is often modified by the posture of the dolphins involved. Direct or perpendicular approaches are usually observed during aggressive exchanges, while approaches from behind or at oblique angles seem to be less threatening. We should remember this when we swim among dolphins! Visual cues, such as body coloration or posture, are also important avenues for communication among dolphins. All these signals combine in various ways to communicate vital information such as age, gender, sexual responsiveness, identification and activity.
Social Structure
Dolphins are social animals with groups ranging in size from two to 15 animals, and often containing more. Many studied dolphin communities seem to be "matrilineal", consisting of females and their accumulated offspring, or sisters and other females. Calves within these groups will often develop stable relationships with each other over a period of years.
Subadult males will usually leave these groups and form "bachelor" groups that often remain together. Sexually mature males may form partnerships or coalitions with other males and seem to move throughout the female groups. There is no evidence for strong social bonds between male and female pairs.
Play is an integral part of social relations for dolphins. They are frequently seen riding the bow wave or stern wake of boats and "surfing" on waves. Both juvenile and adult dolphins often chase each other and toss things to one another, such as seaweed. Jumping from the water's surface and breaching can also indicate excitement. Play is often an extremely important mechanism for learning and for practicing skills that assist in a dolphin's long term survival
Toothed whales comprise a large group of the cetaceans, including dolphins, porpoises and the whales with teeth. They demonstrate an incredible range of forms, behavior and lifestyles that reflect their evolutionary history and the variety of environments in which the live.
Many, if not all, toothed whales have the ability to locate their prey using "echolocation". Echolocation clicks, similar to sonar, are intense, short pulses of amplitude-modulated sound. These pulses sound like a series of clicks (similar to a rusty hinge on an opening door) and are produced in the melon, or forehead, of dolphins. Dolphins direct these clicks at objects in their environment: the returning "echoes" are reflections of the emitted clicks after bouncing off the objects.
Many of the toothed whales also produce frequency-modulated pure-tone sounds, e.g., whistles. These sounds are probably function primarily in the exchange of information among individuals. Communication is an important aspect of any society or collection of individuals. Dolphins and whales communicate with the variety of sounds they produce as well as with body posture, movement, and physical contact behavior.
Communication
Dolphins are thought to be highly intelligent creatures due to their relatively large brain size and apparently complex communication systems. Such conclusions, however, remain the subject of debate. These animals must not be measured according to how close they come to equaling human intelligence and development, but rather accepted and appreciated for what they are.
Body Contact
Dolphins have a well-developed tactile sense. They are often in contact with traveling companions. Body contact is an important component in communication, and is accomplished through rubbing, petting, and hitting among other forms of touch. Some examples include the contact between a mother/calf pair, pectoral fin to pectoral fin rubbing, swimming while remaining in contact with another, and rubbing bodies. Mutual pectoral fin rubs may be exchanged by two dolphins that have just come together. These may be a sort of greeting, similar to a handshake or hug between two people. Or, sometimes dolphins swim a distance and one individual rests its pectoral fin along the side of a second individual. This behavior, called contact position, may be a signal to others that these two are close friends. It could also mean that the first dolphin wants a favor, so to speak, from the second.
Body contact is often modified by the posture of the dolphins involved. Direct or perpendicular approaches are usually observed during aggressive exchanges, while approaches from behind or at oblique angles seem to be less threatening. We should remember this when we swim among dolphins! Visual cues, such as body coloration or posture, are also important avenues for communication among dolphins. All these signals combine in various ways to communicate vital information such as age, gender, sexual responsiveness, identification and activity.
Social Structure
Dolphins are social animals with groups ranging in size from two to 15 animals, and often containing more. Many studied dolphin communities seem to be "matrilineal", consisting of females and their accumulated offspring, or sisters and other females. Calves within these groups will often develop stable relationships with each other over a period of years.
Subadult males will usually leave these groups and form "bachelor" groups that often remain together. Sexually mature males may form partnerships or coalitions with other males and seem to move throughout the female groups. There is no evidence for strong social bonds between male and female pairs.
Play is an integral part of social relations for dolphins. They are frequently seen riding the bow wave or stern wake of boats and "surfing" on waves. Both juvenile and adult dolphins often chase each other and toss things to one another, such as seaweed. Jumping from the water's surface and breaching can also indicate excitement. Play is often an extremely important mechanism for learning and for practicing skills that assist in a dolphin's long term survival
Monday, September 20, 2004
Some Suggested Manners for Dolphin-Watching and Dolphin-Swimming Participants
Over the past 15 years human interest in dolphins and whales has increased at what seems to be an exponential rate. This trend shows no sign of declining. With our heightened interest has come a desire to observe and interact with dolphins and whales in their natural environment. A positive effect of this is a renewed sense to protect the environment.
It is important to realize that the ocean is not our home, but our playground. It is, however, home to dolphins, whales, and numerous other marine organisms. We are guests and should act accordingly. The list below presents some guidelines and suggestions that we encourage anyone planning to interact with dolphins or whales to follow - whether you are watching at the surface or swimming with dolphins underwater. The guidelines are provided for your safety as well as for the safety of the dolphins and whales. Even though equipped with a huge smile and a seemingly forever-harmonious disposition, dolphins and whales are wild animals. Always remember this fact.
DO NOT TOUCH the dolphins. If the dolphins want physical contact with people, they will initiate it. If you try to touch one dolphin, then all the dolphins invariably leave the area. Not only does this adversely affect dolphin behavior but it irritates the other people with your group since everyone loses on the swim.
DO NOT CHASE or swim after, or follow the dolphins away from the group of humans. They are incredibly graceful and powerful swimmers. There is no way any human could keep up with them. Swimming after them when they move off simply forces them to move a bit further away.
ALWAYS LISTEN to your Dolphin Guide or Captain. Not only do they have many hours (and often years) experience around the dolphins, they also have much experience on the water. Most of them are interested to answer questions and share their knowledge.
The ocean is an amazing entity! Your trip may have started out just to see dolphins, but you can actually gain much more and learn about the ocean, currents, wind and other animals in the area, like Streaked Shearwaters and flying fish.
Remember your limits! Don't push yourself - enjoy your trip. If you are not confident about your skin diving abilities, or don't feel like going in the water, DON'T DO IT. You can have a lot of fun watching from the boat.
LOOK DOWN when actually in the water. The dolphins will often swim right underneath you or from behind you.
Be willing to snorkel below the surface but be careful and aware of your own limitations. If you feel uncomfortable in the water, ask your Dolphin Guide for suggestions. Snorkeling is a fun sport, but only when one is comfortable.
When surfacing to breathe, look up to avoid any potential objects in your way.
BE AWARE of the boat when you are in the water. Be ready to enter the water and be ready to exit when told to do so. When entering, go feet first, holding your mask against your face with your snorkel in your mouth. Generally, look up and forward to see the boat. With waves, it can be difficult to see the boat from underwater.
Dolphin swimming and watching is fun, but tiring. Try to be in good condition to skin dive. The more experience you have in the water, the better time you will have.
If you are an experienced skin diver, you may want to try one or more of the following tips:
The best approaches underwater to swimming dolphins seem to be from an angle that is from the side or at about 45° (roughly). Direct or head-to-head approaches or fast swims at 90° to others usually signify aggressive activity.
Try dolphin kicking (like butterfly swimming with both legs together). It is fast but requires a lot of energy.
Underwater turns, circle swimming and flips may indicate play to dolphins. They may try to imitate you doing these behaviors.
Use your body as a tool to communicate. Remember the streamlined shape of the dolphins.
REMEMBER, the dolphins seem interested in us and therefore come to swim around us. We are visitors to their world and should not abuse the welcome they extend to us. So, let's reciprocate by not infringing on their activity and by not polluting the oceans. With these simple guidelines, we can show our respect for the ocean and the creatures that live in it.
(http://www.dolphincommunicationproject.org/conduct.asp)
It is important to realize that the ocean is not our home, but our playground. It is, however, home to dolphins, whales, and numerous other marine organisms. We are guests and should act accordingly. The list below presents some guidelines and suggestions that we encourage anyone planning to interact with dolphins or whales to follow - whether you are watching at the surface or swimming with dolphins underwater. The guidelines are provided for your safety as well as for the safety of the dolphins and whales. Even though equipped with a huge smile and a seemingly forever-harmonious disposition, dolphins and whales are wild animals. Always remember this fact.
DO NOT TOUCH the dolphins. If the dolphins want physical contact with people, they will initiate it. If you try to touch one dolphin, then all the dolphins invariably leave the area. Not only does this adversely affect dolphin behavior but it irritates the other people with your group since everyone loses on the swim.
DO NOT CHASE or swim after, or follow the dolphins away from the group of humans. They are incredibly graceful and powerful swimmers. There is no way any human could keep up with them. Swimming after them when they move off simply forces them to move a bit further away.
ALWAYS LISTEN to your Dolphin Guide or Captain. Not only do they have many hours (and often years) experience around the dolphins, they also have much experience on the water. Most of them are interested to answer questions and share their knowledge.
The ocean is an amazing entity! Your trip may have started out just to see dolphins, but you can actually gain much more and learn about the ocean, currents, wind and other animals in the area, like Streaked Shearwaters and flying fish.
Remember your limits! Don't push yourself - enjoy your trip. If you are not confident about your skin diving abilities, or don't feel like going in the water, DON'T DO IT. You can have a lot of fun watching from the boat.
LOOK DOWN when actually in the water. The dolphins will often swim right underneath you or from behind you.
Be willing to snorkel below the surface but be careful and aware of your own limitations. If you feel uncomfortable in the water, ask your Dolphin Guide for suggestions. Snorkeling is a fun sport, but only when one is comfortable.
When surfacing to breathe, look up to avoid any potential objects in your way.
BE AWARE of the boat when you are in the water. Be ready to enter the water and be ready to exit when told to do so. When entering, go feet first, holding your mask against your face with your snorkel in your mouth. Generally, look up and forward to see the boat. With waves, it can be difficult to see the boat from underwater.
Dolphin swimming and watching is fun, but tiring. Try to be in good condition to skin dive. The more experience you have in the water, the better time you will have.
If you are an experienced skin diver, you may want to try one or more of the following tips:
The best approaches underwater to swimming dolphins seem to be from an angle that is from the side or at about 45° (roughly). Direct or head-to-head approaches or fast swims at 90° to others usually signify aggressive activity.
Try dolphin kicking (like butterfly swimming with both legs together). It is fast but requires a lot of energy.
Underwater turns, circle swimming and flips may indicate play to dolphins. They may try to imitate you doing these behaviors.
Use your body as a tool to communicate. Remember the streamlined shape of the dolphins.
REMEMBER, the dolphins seem interested in us and therefore come to swim around us. We are visitors to their world and should not abuse the welcome they extend to us. So, let's reciprocate by not infringing on their activity and by not polluting the oceans. With these simple guidelines, we can show our respect for the ocean and the creatures that live in it.
(http://www.dolphincommunicationproject.org/conduct.asp)
Dolphins Whistle "hello" - August 24, 2000 - BBC
Wild dolphins greet each of their pals using individual whistle signatures.
Until now this sort of behaviour has only been found in birds and humans.
Previous research with captive dolphins shows that each one has a unique whistle and can mimic another dolphin's whistle perfectly after hearing it just once.
Biologist Dr Vincent Janik at the University of St Andrews in Scotland decided to investigate how bottle nose dolphins interact in the wild.
He recorded nearly two thousand whistles from dolphin pods off the Scottish coast.
So as not to disturb the dolphins with noisy boats, he used six underwater microphones and a computer-based method for locating individual vocalists. Human listeners then identified matching whistles.
First step to language
Dr Janik concluded that the dolphins were responding to each other by mimicking an individual's call back. Such interactions with learned signals are thought to be a first step toward the evolution of real language.
Communication between dolphins seems to be quite sophisticated yet no one really knows what they say to each other.
Dolphin saves boy's life - Boy pushed back to his boat after fall
A friendly dolphin has saved a teenage boy from drowning.
Non-swimmer Davide Ceci, 14, was within minutes of death when dolphin Filippo came to his rescue.
The friendly 61-stone creature has been a popular tourist attraction off Manfredonia in south-east Italy for two years.
But now he is a local hero after saving Davide from the Adriatic when he fell from his father's boat.
While Emanuele Ceci was still unaware his son had fallen into the waves, Filippo was pushing him up out of the water to safety.
Davide said: "When I realised it was Filippo pushing me, I grabbed on to him."
The dolphin bore down on the boat and got close enough for Davide's father to grab his gasping son.
Davide's mother Signora Ceci said: "It is a hero, it seems impossible an animal could have done something like that, to feel the instinct to save a human life."
Filippo has lived in the waters off Manfredonia since he became separated from a visiting school of dolphins.
Maritime researcher Dr Giovanna Barbieri said: "Filippo seems not to have the slightest fear of humans. I'm not surprised he should have done such a wonderful thing as to save a human."
(August 30, 2000 - Daily Record - Scotland )
Dolphin Researchers Make Breakthrough in Hong Kong - June 27, 2001 - Reuters
The world's first artificially conceived dolphins have been born in tiny Hong Kong, marking a major step in efforts to reduce inbreeding in captivity and preserve endangered dolphin species.
The two calves, which have yet to be named, were born nine days apart in May, scientists in Hong Kong said.
Mothers Ada and Gina, both bottlenose dolphins, made history last June when they became the world's first dolphins to be successfully inseminated artificially.
Using ultrasound, scientists from Hong Kong's Polytechnic University, the territory's Ocean Park aquarium and Seaworld in the United States were able to accurately predict ovulation in dolphins for the first time.
Dolphins have very irregular ovulation cycles, making artificial insemination exceptionally difficult, and past attempts in the United States have failed.
The calves, one female and one male, have been keeping close by their mothers, said Fiona Brook, head of the 12-year-old project and an associate professor at the Polytechnic University.
``They are big, fat, healthy calves,'' Brook told Reuters.
NEW HOPE
While dolphins in general do not have problems reproducing, inbreeding can quickly become a problem with dolphins in captivity, which produces genetically weaker offspring.
Artificial insemination broadens the genetic pool and reduces the need to bring in dolphins from the wild.
Ada, 17, and Gina, 20, from Indonesian waters, were impregnated just over a year ago with sperm from 17-year-old Molly, also a resident at Ocean Park.
The technology also could be used to help endangered dolphin species.
Scientists and environmentalists in Hong Kong are increasingly concerned about pink dolphins, also known as Chinese White Dolphins, which are facing extinction because of pollution and overfishing.
Marine biologists in Hong Kong believe there are only about 150 pink dolphins left in China's nearby Pearl River estuary, while 1,000 may still survive in southern Chinese waters including areas off Macau and Hong Kong.
Scientists in Hong Kong now want to experiment with artificial insemination using sperm that had been frozen, which could further enlarge the genetic pool.
"If we can do it using frozen sperm, what that will allow is we can extend the genetic pool worldwide. We can bring frozen sperm from anywhere in the world and inseminate females here or we can send semen here to anywhere else in the world,'' Brook said.
Bush Administration Double-Speak
Bush's Commerce Secretary Decision Betrays Dolphins, U.S. Tuna Industry, and American Consumers
Submitted by International Marine Mammal Project
December 31, 2002
Contacts:
David Phillips (415) 788-3666
Mark J. Palmer (530) 758-6022 or (415) 788-3666 x139
San Francisco, CA -- Earth Island Institute today condemned the decision by President Bush's Commerce Secretary, Donald Evans, to weaken the standards for the "Dolphin Safe" label on American tuna cans.
"The Bush Administration's claim that chasing and netting of dolphins is 'safe' for dolphins is fraudulent and must be overturned by the courts," stated David Phillips, Director of Earth Island Institute's International Marine Mammal Project. "The Bush Administration is selling out dolphins in order to reward Mexican tuna millionaires. If the Secretary's decision is left intact, 20-40,000 dolphins each year will be sacrificed, and falsely labeled Mexican tuna will be on the U.S. market as 'Dolphin Safe.' We cannot allow that to occur."
Earlier in December, Earth Island Institute released a Report by the Commerce Department's own scientists showing that the chasing and netting of dolphins was harming dolphin populations and separating dolphin babies from their mothers.
Environmentalists contend that the U.S. Commerce Secretary's decision, which now allows a new weaker definition of "Dolphin Safe", is arbitrary and capricious. The successful federal "Dolphin Safe" tuna program is being jeopardized by the federal government's weakening of U.S. dolphin protection laws to accommodate tuna millionaires in Mexico and other countries in the name of "free trade," not science. The decision by Commerce further ignores two federal court rulings against a similar decision, made in 1999 by former Commerce Secretary William Daley, in the court case "Brower v. Evans."
Added Phillips: "We will be seeing the Bush Administration in court, as this decision is clearly illegal."
Groups opposing the weakened "Dolphin Safe" tuna label include biologist and dolphin activist Samuel LaBudde, Jean-Michel Cousteau, the Humane Society of the United States, Sierra Club, American Society for the Prevention of Cruelty to Animals (ASPCA), Defenders of Wildlife, International Wildlife Coalition, Animal Welfare Institute, Animal Fund, Oceanic Society, and Friends of the Earth.
Before today's action by the Secretary, the "Dolphin Safe" label could not be used for any tuna caught by chasing and netting of dolphins (e.g. "Dolphin Safe" meant no encirclement of dolphins with deadly nets). Tuna fishermen in the Eastern Tropical Pacific (ETP) target dolphins because tuna and dolphins form mixed schools. Since 1990 and the advent of the "Dolphin Safe" tuna program, dolphin deaths have decreased by 98% in the ETP.
However, U.S. Commerce Secretary Don Evans has made the finding, contrary to all available scientific information, that chasing and netting dolphins does NOT cause significant adverse impacts. In fact, biologists with the National Marine Fisheries Service (NMFS), a division of the Dept. of Commerce, have determined that depleted dolphin populations are NOT recovering in the ETP, and that the cause is almost certainly due to the deadly nets of the tuna fishing industry. NMFS scientists determined that chasing and netting dolphins separates mothers from dependent calves and that the chase and capture causes severe physiological stress. Many dolphins suffer injuries in the nets and die after release, but are not counted by the on-board observer. There are also reports that on-board observers are reporting false dolphin mortality numbers, either through intimidation or bribery, and that smaller vessels without observers are illegally setting nets and drowning dolphins, as occurred this spring in the Galapagos Islands.
The Secretary's action automatically weakens the standards by which tuna is judged to be "Dolphin Safe" to now allow chase, harassment, netting, injuring, and even killing of dolphins when catching tuna, so long as an on-board observer reports no dolphins killed outright or "seriously injured." Tuna caught by this destructive method of chasing and netting dolphins can now be labeled "Dolphin Safe." U.S. tuna fishermen no longer set nets on dolphins, and the major U.S. tuna processors -- StarKist, Bumble Bee, and Chicken of the Sea -- have pledged they will not buy tuna caught by chasing and netting dolphins. The primary beneficiary of the Secretary's decision is Mexico, although Venezuela, Colombia, and several other Latin nations continue to chase and net dolphins to catch tuna. Only Mexico has so far been certified by the Department of Commerce to import tuna.
It is believed that many of the Mexican, Venezuelan, and Colombian tuna companies are also involved in large-scale smuggling of cocaine and other illegal drugs, using the large tuna clippers to carry tons of drugs from the Colombian cartels into Mexican waters. More than two-thirds of U.S. illegal cocaine supply is smuggled across the border through Mexico. Several large tuna purse seiners have been caught by U.S. Coast Guard authorities off the coast of Mexico with record loads of cocaine hidden on board. In Venezuela, cocaine is called "atun blanco" or "white tuna."
"The American public deserves to know the truth about how tuna was caught," Phillips stated. "The Secretary's decision to deliberately lie to American consumers benefits a small handful of Mexican tuna millionaires and drug lords, who can now import tuna to the U.S. using a phony "Dolphin Safe" label. All of the major U.S. and European tuna processors have pledged not to buy or sell such tuna. American consumers won't buy tuna stained by the blood of dolphins."
* * * *
Earth Island Institute is a nonprofit educational organization dedicated to protecting the diversity of life on Earth. The International Marine Mammal Project works to protect whales, dolphins and other marine mammals around the world.
VIDEO AVAILABLE: Broadcast quality video footage by Samuel LaBudde of the devastating effects of tuna nets on dolphins is available by calling Earth Island (415) 788-3666.
Submitted by International Marine Mammal Project
December 31, 2002
Contacts:
David Phillips (415) 788-3666
Mark J. Palmer (530) 758-6022 or (415) 788-3666 x139
San Francisco, CA -- Earth Island Institute today condemned the decision by President Bush's Commerce Secretary, Donald Evans, to weaken the standards for the "Dolphin Safe" label on American tuna cans.
"The Bush Administration's claim that chasing and netting of dolphins is 'safe' for dolphins is fraudulent and must be overturned by the courts," stated David Phillips, Director of Earth Island Institute's International Marine Mammal Project. "The Bush Administration is selling out dolphins in order to reward Mexican tuna millionaires. If the Secretary's decision is left intact, 20-40,000 dolphins each year will be sacrificed, and falsely labeled Mexican tuna will be on the U.S. market as 'Dolphin Safe.' We cannot allow that to occur."
Earlier in December, Earth Island Institute released a Report by the Commerce Department's own scientists showing that the chasing and netting of dolphins was harming dolphin populations and separating dolphin babies from their mothers.
Environmentalists contend that the U.S. Commerce Secretary's decision, which now allows a new weaker definition of "Dolphin Safe", is arbitrary and capricious. The successful federal "Dolphin Safe" tuna program is being jeopardized by the federal government's weakening of U.S. dolphin protection laws to accommodate tuna millionaires in Mexico and other countries in the name of "free trade," not science. The decision by Commerce further ignores two federal court rulings against a similar decision, made in 1999 by former Commerce Secretary William Daley, in the court case "Brower v. Evans."
Added Phillips: "We will be seeing the Bush Administration in court, as this decision is clearly illegal."
Groups opposing the weakened "Dolphin Safe" tuna label include biologist and dolphin activist Samuel LaBudde, Jean-Michel Cousteau, the Humane Society of the United States, Sierra Club, American Society for the Prevention of Cruelty to Animals (ASPCA), Defenders of Wildlife, International Wildlife Coalition, Animal Welfare Institute, Animal Fund, Oceanic Society, and Friends of the Earth.
Before today's action by the Secretary, the "Dolphin Safe" label could not be used for any tuna caught by chasing and netting of dolphins (e.g. "Dolphin Safe" meant no encirclement of dolphins with deadly nets). Tuna fishermen in the Eastern Tropical Pacific (ETP) target dolphins because tuna and dolphins form mixed schools. Since 1990 and the advent of the "Dolphin Safe" tuna program, dolphin deaths have decreased by 98% in the ETP.
However, U.S. Commerce Secretary Don Evans has made the finding, contrary to all available scientific information, that chasing and netting dolphins does NOT cause significant adverse impacts. In fact, biologists with the National Marine Fisheries Service (NMFS), a division of the Dept. of Commerce, have determined that depleted dolphin populations are NOT recovering in the ETP, and that the cause is almost certainly due to the deadly nets of the tuna fishing industry. NMFS scientists determined that chasing and netting dolphins separates mothers from dependent calves and that the chase and capture causes severe physiological stress. Many dolphins suffer injuries in the nets and die after release, but are not counted by the on-board observer. There are also reports that on-board observers are reporting false dolphin mortality numbers, either through intimidation or bribery, and that smaller vessels without observers are illegally setting nets and drowning dolphins, as occurred this spring in the Galapagos Islands.
The Secretary's action automatically weakens the standards by which tuna is judged to be "Dolphin Safe" to now allow chase, harassment, netting, injuring, and even killing of dolphins when catching tuna, so long as an on-board observer reports no dolphins killed outright or "seriously injured." Tuna caught by this destructive method of chasing and netting dolphins can now be labeled "Dolphin Safe." U.S. tuna fishermen no longer set nets on dolphins, and the major U.S. tuna processors -- StarKist, Bumble Bee, and Chicken of the Sea -- have pledged they will not buy tuna caught by chasing and netting dolphins. The primary beneficiary of the Secretary's decision is Mexico, although Venezuela, Colombia, and several other Latin nations continue to chase and net dolphins to catch tuna. Only Mexico has so far been certified by the Department of Commerce to import tuna.
It is believed that many of the Mexican, Venezuelan, and Colombian tuna companies are also involved in large-scale smuggling of cocaine and other illegal drugs, using the large tuna clippers to carry tons of drugs from the Colombian cartels into Mexican waters. More than two-thirds of U.S. illegal cocaine supply is smuggled across the border through Mexico. Several large tuna purse seiners have been caught by U.S. Coast Guard authorities off the coast of Mexico with record loads of cocaine hidden on board. In Venezuela, cocaine is called "atun blanco" or "white tuna."
"The American public deserves to know the truth about how tuna was caught," Phillips stated. "The Secretary's decision to deliberately lie to American consumers benefits a small handful of Mexican tuna millionaires and drug lords, who can now import tuna to the U.S. using a phony "Dolphin Safe" label. All of the major U.S. and European tuna processors have pledged not to buy or sell such tuna. American consumers won't buy tuna stained by the blood of dolphins."
* * * *
Earth Island Institute is a nonprofit educational organization dedicated to protecting the diversity of life on Earth. The International Marine Mammal Project works to protect whales, dolphins and other marine mammals around the world.
VIDEO AVAILABLE: Broadcast quality video footage by Samuel LaBudde of the devastating effects of tuna nets on dolphins is available by calling Earth Island (415) 788-3666.
Genetic Enhancement Centre for Coastal Ecosystem (Anticipatory Research Programme for Meeting the Challenge of a Potential Rise in Sea Level)
Coastal ecosystem suffers from increasing population pressure, low agricultural productivity, depleting natural resources and increasing environmental degradation. These problems may worsen in the years to come because of the rise in sea level as a result of global warming. The center undertakes anticipatory research programmes in the area of genetic resources characterization, conservation and enhancement employing state of art modern biotechnological tools.
The objectives of the center are to
Mangroves are salt tolerant plant communities occupying the coastal estuarine regions of the tropics. They serve as a vital link between terrestrial and aquatic ecosystems and provide livelihood and ecological security for the coastal communities. They comprise of about 60 species, ecologically adapted to the region. Despite their ecological and economic potential, no information is available on genetic composition of these species groups. MSSRF is the first institution worldwide to have undertaken modern molecular marker based analysis of mangroves. These studies have provided substantial information for developing unambiguous identification systems for individual species, elucidating nature and extent of genetic diversity at intra- and inter population level, depicting interspecies relationship and establishing phylogenetic trends in mangroves. Developing location specific conservation strategy and establishment of mangrove genetic resources centre are among the implications of the ongoing efforts on genetic mapping of the mangroves.
MSSRF was the first to propose the concept that mangroves can be invaluable donors of breeding crop genotypes adapted to coastal salinity through recombinant DNA technology. Identification and isolation of novel genetic combinations with implications to abiotic stress were undertaken from the widely distributed mangrove species, Avicennia marina and the wild rice Porteresia coarctata. Enriched gene libraries constructed from these two species are used for identification and isolation of stress tolerant genes. Many novel genetic combinations have been identified, sequenced and characterized from these libraries. Efforts for identification of unique genes in mangroves have also been undertaken using large scale genome sequencing and differential expression analysis. As many as 2000 partial gene sequences from mangroves have been deposited in World wide databases, and thrs has been the first ever bulk submission from any laboratory in India.
Developing crop varieties with resistance to coastal salinity is among the major objectives of the programme. Some of the isolated genes from mangroves were characterised and analyzed for their expression levels in varying saline conditions. Methodologies for construction of vectors for transformation and transformation systems have been established in Tobacco, Rice, Blackgram and Mustard. Transgenic crop plants in the species are in different stages of development. Their performance and safety aspects are being studied as per the stipulated biosafety guidelines and monitoring by the Institutional Biosafety and Bioethics Committee (IBSC) at MSSRF. A containment facility for safety assessment of the transgenics has been developed at the Foundation.
An integrated approach to gene isolation and development of transgenics in locally adapted cultivars and integration of pre-breeding with participatory breeding will help to strengthen the stability and sustainability of the fragile coastal ecosystem on the one hand, and the productivity and profitability of the coastal farming systems, on the other. We are grateful to the Department of Biotechnology, Government of India for their continued financial and technical support over the last 10 years. But for their sustained support, this research of great significance to shaping a better future for coastal communities world-wide would not have been possible.
The objectives of the center are to
- genetically characterize coastal bioresources, in particular mangroves;
- identify, isolate and characterize novel genetic combinations from mangroves;
- provide characterized pre-breeding material; and
- develop location specific crop varieties offering resistance/ tolerance to coastal salinity.
Mangroves are salt tolerant plant communities occupying the coastal estuarine regions of the tropics. They serve as a vital link between terrestrial and aquatic ecosystems and provide livelihood and ecological security for the coastal communities. They comprise of about 60 species, ecologically adapted to the region. Despite their ecological and economic potential, no information is available on genetic composition of these species groups. MSSRF is the first institution worldwide to have undertaken modern molecular marker based analysis of mangroves. These studies have provided substantial information for developing unambiguous identification systems for individual species, elucidating nature and extent of genetic diversity at intra- and inter population level, depicting interspecies relationship and establishing phylogenetic trends in mangroves. Developing location specific conservation strategy and establishment of mangrove genetic resources centre are among the implications of the ongoing efforts on genetic mapping of the mangroves.
MSSRF was the first to propose the concept that mangroves can be invaluable donors of breeding crop genotypes adapted to coastal salinity through recombinant DNA technology. Identification and isolation of novel genetic combinations with implications to abiotic stress were undertaken from the widely distributed mangrove species, Avicennia marina and the wild rice Porteresia coarctata. Enriched gene libraries constructed from these two species are used for identification and isolation of stress tolerant genes. Many novel genetic combinations have been identified, sequenced and characterized from these libraries. Efforts for identification of unique genes in mangroves have also been undertaken using large scale genome sequencing and differential expression analysis. As many as 2000 partial gene sequences from mangroves have been deposited in World wide databases, and thrs has been the first ever bulk submission from any laboratory in India.
Developing crop varieties with resistance to coastal salinity is among the major objectives of the programme. Some of the isolated genes from mangroves were characterised and analyzed for their expression levels in varying saline conditions. Methodologies for construction of vectors for transformation and transformation systems have been established in Tobacco, Rice, Blackgram and Mustard. Transgenic crop plants in the species are in different stages of development. Their performance and safety aspects are being studied as per the stipulated biosafety guidelines and monitoring by the Institutional Biosafety and Bioethics Committee (IBSC) at MSSRF. A containment facility for safety assessment of the transgenics has been developed at the Foundation.
An integrated approach to gene isolation and development of transgenics in locally adapted cultivars and integration of pre-breeding with participatory breeding will help to strengthen the stability and sustainability of the fragile coastal ecosystem on the one hand, and the productivity and profitability of the coastal farming systems, on the other. We are grateful to the Department of Biotechnology, Government of India for their continued financial and technical support over the last 10 years. But for their sustained support, this research of great significance to shaping a better future for coastal communities world-wide would not have been possible.
Secret Dolphin Study Report Released
Earth Island Institute Releases Bush Administration Report Showing Dolphin Slaughter in Tuna Nets Continues Submitted by International Marine Mammal Project December 5, 2002
PRESS RELEASE
Contacts: Earth Island Institute
David Phillips (415) 788-3666
Mark J. Palmer (415) 788-3666
(San Francisco) - Earth Island Institute today released a secret U.S. government report and posted a copy on the Earth Island Website at www.earthisland.org/immp/secret_report.pdf (Size: ~1 MB). Prepared by scientists in the Bush Administration’s National Marine Fisheries Service (NMFS), the report reveals that thousands of dolphins, especially baby dolphins, are still dying in tuna nets in the Eastern Tropical Pacific (ETP), largely in tuna fleets owned by tuna millionaires in Mexico, Venezuela, Colombia, and other nations. Earth Island believes the Bush Administration is hiding this damning report because it undermines its attempt to falsely label dolphin-deadly tuna as “Dolphin Safe.”
“For the first time, NMFS has officially acknowledged the massive and previously uncounted killing of baby dolphins that are separated from their mothers during chase and capture by tuna vessels using mile-long nets,” stated David Phillips, Director of Earth Island Institute’s International Marine Mammal Project. “This is a shocking and tragic revelation.”
“This Report on NMFS scientists’ dolphin research clearly shows that the technique favored by the Mexican tuna fleet and other nations to catch tuna causes significant harm to dolphins,” Phillips continued. “The Secretary of Commerce would have to defy science, common sense, and the law in order to weaken the U.S. federal standards for the use of the ‘Dolphin Safe’ tuna label in light of the report. This secret report reveals that dolphin numbers are severely depleted and not recovering. Weakening the ‘Dolphin Safe’ tuna label would simply increase the slaughter.”
The secret report, an accumulation of government research conducted from 1997 to 2002, includes the following new findings:
Despite low reported dolphin kills from the tuna fleets, dolphin populations remain seriously depleted. Eastern Spinner dolphins remain at only 35% of their former numbers; Northeastern Offshore Spotted dolphins are at only 20% of their former numbers;
More importantly, the research shows that dolphins are NOT recovering as expected. By some calculations, the populations may still be declining. By one analysis, it would take 65 years for depleted Eastern Spinner dolphins to recover, while depleted Northeastern Offshore Spotted dolphins would take 78 years to recover. Another analysis, equally supported by the data, projects that neither species would recover after 200 years.
At least an additional 6-10% of Eastern Spinner dolphin mortality and an additional 10-15% of Northeastern Offshore Spotted dolphin mortality is occurring due to separation of dependent baby dolphins from their mothers during the chasing and netting process, and the percentage is likely higher.
Nets are set on schools of dolphins 7,500 times EACH YEAR, resulting in the chasing of 9.3 million dolphins EACH YEAR and the capture in nets of 2.3 million dolphins EACH YEAR. Individual dolphins in the ETP are chased an average of 5.6 times EACH YEAR and captured an average of 0.7 times EACH YEAR for depleted Eastern Spinner dolphins and chased 10.6 times EACH YEAR and captured 3.2 times EACH YEAR for depleted Northeastern Offshore Spotted dolphins. The Report states that physiological stress (resulting in decreased births, impaired health, and deaths of dolphins) is a plausible explanation for the lack of recovery of depleted dolphin populations.
There is no evidence of any environmental changes that could account for the magnitude of the lack of recovery of dolphin populations. Indeed, the carrying capacity of the ETP for dolphins would have to decrease three- to four-fold in order to account for the lack of recovery of dolphins.
In conclusion, the tuna fishery is clearly the reason for the dolphins’ lack of recovery. No other explanation fits the research data or the facts.
The Secretary of Commerce has until the end of December to make a finding as to whether the chasing and netting of dolphins causes “significant adverse impacts” on depleted dolphin populations. A finding of “no significant adverse impacts” would automatically weaken the standards for use of the “Dolphin Safe” tuna label, allowing a flood of falsely labeled imported tuna from Latin American nations.
“The American public deserves to know the truth about how tuna was caught,” Phillips stated. “The Bush Administration is sitting on this explosive report on the dangers of chasing and netting dolphins. The Secretary of Commerce is posed to decide to deliberately lie to American consumers to benefit a small handful of Mexican tuna millionaires and drug lords, who would be able import tuna to the U.S. using a phony “Dolphin Safe” label. All of the major U.S. and European tuna processors have pledged not to buy or sell such tuna. American consumers won’t buy tuna stained by the blood of dolphins!”
Earth Island Institute is a nonprofit educational organization dedicated to protecting the diversity of life on Earth. The International Marine Mammal Project works to protect whales, dolphins and other marine mammals around the world. VIDEO AVAILABLE: Broadcast quality video footage by Samuel LaBudde of the devastating effects of tuna nets on dolphins is available by calling Earth Island (415) 788-3666.
For more information contact:
International Marine Mammal Project
David Phillips (415) 788-3666
Mark J. Palmer (415) 788-3666
(http://www.oneworld.net/external/?url=http%3A%2F%2Fwww.earthisland.org%2Fnews%2Fnew_news.cfm%3FnewsID%3D292)
PRESS RELEASE
Contacts: Earth Island Institute
David Phillips (415) 788-3666
Mark J. Palmer (415) 788-3666
(San Francisco) - Earth Island Institute today released a secret U.S. government report and posted a copy on the Earth Island Website at www.earthisland.org/immp/secret_report.pdf (Size: ~1 MB). Prepared by scientists in the Bush Administration’s National Marine Fisheries Service (NMFS), the report reveals that thousands of dolphins, especially baby dolphins, are still dying in tuna nets in the Eastern Tropical Pacific (ETP), largely in tuna fleets owned by tuna millionaires in Mexico, Venezuela, Colombia, and other nations. Earth Island believes the Bush Administration is hiding this damning report because it undermines its attempt to falsely label dolphin-deadly tuna as “Dolphin Safe.”
“For the first time, NMFS has officially acknowledged the massive and previously uncounted killing of baby dolphins that are separated from their mothers during chase and capture by tuna vessels using mile-long nets,” stated David Phillips, Director of Earth Island Institute’s International Marine Mammal Project. “This is a shocking and tragic revelation.”
“This Report on NMFS scientists’ dolphin research clearly shows that the technique favored by the Mexican tuna fleet and other nations to catch tuna causes significant harm to dolphins,” Phillips continued. “The Secretary of Commerce would have to defy science, common sense, and the law in order to weaken the U.S. federal standards for the use of the ‘Dolphin Safe’ tuna label in light of the report. This secret report reveals that dolphin numbers are severely depleted and not recovering. Weakening the ‘Dolphin Safe’ tuna label would simply increase the slaughter.”
The secret report, an accumulation of government research conducted from 1997 to 2002, includes the following new findings:
Despite low reported dolphin kills from the tuna fleets, dolphin populations remain seriously depleted. Eastern Spinner dolphins remain at only 35% of their former numbers; Northeastern Offshore Spotted dolphins are at only 20% of their former numbers;
More importantly, the research shows that dolphins are NOT recovering as expected. By some calculations, the populations may still be declining. By one analysis, it would take 65 years for depleted Eastern Spinner dolphins to recover, while depleted Northeastern Offshore Spotted dolphins would take 78 years to recover. Another analysis, equally supported by the data, projects that neither species would recover after 200 years.
At least an additional 6-10% of Eastern Spinner dolphin mortality and an additional 10-15% of Northeastern Offshore Spotted dolphin mortality is occurring due to separation of dependent baby dolphins from their mothers during the chasing and netting process, and the percentage is likely higher.
Nets are set on schools of dolphins 7,500 times EACH YEAR, resulting in the chasing of 9.3 million dolphins EACH YEAR and the capture in nets of 2.3 million dolphins EACH YEAR. Individual dolphins in the ETP are chased an average of 5.6 times EACH YEAR and captured an average of 0.7 times EACH YEAR for depleted Eastern Spinner dolphins and chased 10.6 times EACH YEAR and captured 3.2 times EACH YEAR for depleted Northeastern Offshore Spotted dolphins. The Report states that physiological stress (resulting in decreased births, impaired health, and deaths of dolphins) is a plausible explanation for the lack of recovery of depleted dolphin populations.
There is no evidence of any environmental changes that could account for the magnitude of the lack of recovery of dolphin populations. Indeed, the carrying capacity of the ETP for dolphins would have to decrease three- to four-fold in order to account for the lack of recovery of dolphins.
In conclusion, the tuna fishery is clearly the reason for the dolphins’ lack of recovery. No other explanation fits the research data or the facts.
The Secretary of Commerce has until the end of December to make a finding as to whether the chasing and netting of dolphins causes “significant adverse impacts” on depleted dolphin populations. A finding of “no significant adverse impacts” would automatically weaken the standards for use of the “Dolphin Safe” tuna label, allowing a flood of falsely labeled imported tuna from Latin American nations.
“The American public deserves to know the truth about how tuna was caught,” Phillips stated. “The Bush Administration is sitting on this explosive report on the dangers of chasing and netting dolphins. The Secretary of Commerce is posed to decide to deliberately lie to American consumers to benefit a small handful of Mexican tuna millionaires and drug lords, who would be able import tuna to the U.S. using a phony “Dolphin Safe” label. All of the major U.S. and European tuna processors have pledged not to buy or sell such tuna. American consumers won’t buy tuna stained by the blood of dolphins!”
Earth Island Institute is a nonprofit educational organization dedicated to protecting the diversity of life on Earth. The International Marine Mammal Project works to protect whales, dolphins and other marine mammals around the world. VIDEO AVAILABLE: Broadcast quality video footage by Samuel LaBudde of the devastating effects of tuna nets on dolphins is available by calling Earth Island (415) 788-3666.
For more information contact:
International Marine Mammal Project
David Phillips (415) 788-3666
Mark J. Palmer (415) 788-3666
(http://www.oneworld.net/external/?url=http%3A%2F%2Fwww.earthisland.org%2Fnews%2Fnew_news.cfm%3FnewsID%3D292)
A brief description on Dolphins....
Dolphins are mammals. They breathe air, are warm blooded, give live birth to babies and nurse their young.
The scientific order 'Cetacea' is comprised of whales, dolphins, and porpoises. These aquatic creatures are the most specialized of all mammals, with adaptations that allow them to spend their entire lives in water. Living cetaceans are divided into two distinct suborders, Mysticeti and Odontoceti, which are divided further into a total of thirteen families. The Mysticeti suborder contains those whales, which have baleen plates instead of teeth. A baleen whale feeds by straining water through the baleen, trapping the fish, shrimp, crustaceans, or krill inside its mouth. This suborder is comprised of the largest whale species, including the blue whale, the humpback whale, and the grey whale.
Those cetaceans classified in the suborder Odontoceti are toothed whales, dolphins, and porpoises. They are generally smaller, faster, and more agile than their baleen counterparts. Scientists have identified approximately 80 species of toothed whales, ranging in size from the 60-foot sperm whale to the five-foot harbor porpoise. The various species are incredibly diverse and display a multitude of body shapes, behavior patterns, and lifestyles. Some spend barely any time on the surface, rising occasionally to take a breath; others can leap 20 feet out of the water almost effortlessly. Some species live in the shallows close to shore, some reside in deep oceans, and still others are found only in fresh water rivers. Odontoceti may have anywhere from eight to 250 teeth, and their eyesight ranges from poor to excellent.
Dolphins emit pulses of sound from the melon, a fatty area just below the blowhole. Much like the orientation vocalizations of a bat, these pulses, or clicks, return as echoes when the sound bounces off objects in the dolphin's path. The animal uses the echoes to navigate and to judge the distance to, and location of, prey as small as shrimp. Dolphins also produce whistling sounds when excited or communicating with other dolphins. These sounds arise from the larynx.
Dolphin (aquatic mammal), fast-swimming animal related to whales and porpoises. Sleek and powerful swimmers found in all seas, dolphins are distinguished from porpoises by well-defined, beaklike snouts and conical teeth. The porpoise has a blunt snout, chisel-shaped teeth, and a stouter body.
There are approximately 57 species of dolphins. Most have an elongated beak called a rostrum. The difference between porpoise and dolphin is in the shape of the teeth. Dolphins have cone shaped teeth whereas porpoise have spade shaped teeth. Most porpoise live in colder waters and are smaller than most dolphins, and they have no elongated beak.
The largest of all Dolphins is the Orca, or Killer Whale. It is the most powerful creature that lives in the oceans. It is the fiercest of sea predators and fears no other creature whatsoever.
Typical examples are the bottle-nosed dolphin, a popular performer in seaquariums, and the common dolphin, which inspired many Mediterranean folk legends. Both often appear in open waters, making their characteristic arched bounds, frequently before the bow waves of ships. Several freshwater species inhabit river estuaries in Asia and South America.
The small, graceful tucuxi dolphin has been sighted more than 2000 km (more than 1250 mi) up the Amazon River. The tucuxi, the smallest dolphin, is less than 1.2 m (less than 4 ft) long; the largest, the bottle-nosed dolphin, reaches a length of 3 m (10 ft). The killer whale is considered a dolphin despite its much greater length of 9 m (30 ft). The pilot whale is also considered a type of dolphin.
Dolphins once were hunted commercially, especially for the small quantity of valuable oil extracted from parts of the head and used to lubricate delicate watch mechanisms. Cheaper oils have now been found from other sources, and dolphins are no longer hunted for this reason. Many dolphins, however, become accidentally trapped and drowned in tuna nets; between 1959 and 1972 an estimated 4.8 million dolphins died in this way.
Under pressure from animal rights activists and United States consumers, both domestic and international tuna canners have refused to accept shipments from fishing fleets that do not protect dolphins. Concern has also been expressed about the treatment of dolphins on display in public aquariums and in ³swim with the dolphins² programs. The Marine Mammal Protection Act of 1972, amended in 1988 and 1992, was passed to prevent exploitation of dolphins and related aquatic animals. The National Marine Fisheries Service is the principal regulatory agency.
Behavior
In one day dolphins eat an amount of food, mostly fish and squid, equal to nearly one-third of their weight. Dolphins are swift enough to easily outdistance their prey. They seize their catches with jaws that have from 200 to 250 sharp teeth. Dolphins follow schools of fish in groups of varying size. Some species, such as the Pacific white-sided dolphin, make up aggregations estimated at tens of thousands of members. Less gregarious species, such as the bottle-nosed dolphin, join in groups that often contain only a few members.
Dolphins, like whales, breathe through a blowhole at the top of the head. As they travel they break surface about every two minutes to make a short, explosive exhalation, followed by a longer inhalation before submerging again. The tail, like that of other aquatic mammals, strokes in an up-and-down motion, with the double flukes driving the animal forward; the flippers are used for stabilization. Dolphins are superbly streamlined and can sustain speeds of up to 30 km/h (up to 19 mph), with bursts of more than 40 km/h (more than 25 mph). Their lungs, which are adapted to resist the physical problems created for many animals by rapid changes in pressure, enable them to dive to depths of more than 300 m (more than 1000 ft).
Adults of the bottle-nosed dolphin‹the best-studied species‹come to sexual maturity after 5 to 12 years in females and 9 to 13 years in males. They mate in the spring; after a gestation period of 11 or 12 months, a single calf is born, tail first. Calves swim and breathe minutes after birth; they nurse for up to 18 months. They are able to keep up with the mother by remaining close and taking advantage of the aerodynamic effects of the mother's swimming.
Vocalizations and IntelligencePrint section
Dolphins almost constantly emit either clicking sounds or whistles. The clicks are short pulses of about 300 sounds per second, emitted from a mechanism located just below the blowhole. These clicks are used for the echolocation of objects and are resonated forward by the so-called oily melon, which is located above the forehead and acts as an acoustic lens. Echoes received at the area of the rear of the lower jaw are transmitted by a fat organ in the lower jaw to the middle ear. This echolocation system, similar to that of a bat, enables the dolphin to navigate among its companions and larger objects and to detect fish, squid, and even small shrimp. The whistles are single-toned squeals that come from deeper in the larynx. They are used to communicate alarm, sexual excitement, and perhaps other emotional states.
Because of the ability of dolphins to learn and perform complex tasks in captivity, their continuous communications with one another, and their ability, through training, to approximate the sounds of a few human words, some investigators have suggested that the animals might be capable of learning a true language and communicating with humans. Most authorities, however, agree that although the dolphin's problem-solving abilities put the animal on an intelligence level close to that of primates, no evidence exists that dolphin communications approach the complexity of a true language.
The name dolphin is also applied to food fish of a different genus that have long, continuous dorsal fins. The fish, found worldwide in tropical marine waters, can reach a length of 1.5 m (5 ft).
Scientific classification: Dolphins belong to the suborder Odontoceti of the order Cetacea. The bottle-nosed dolphin is classified as Tursiops truncatus, the common dolphin as Delphinus delphis, and the tucuxi dolphin as Sotalia fluviatilis. The killer whale is classified as Orcinus orca. Pilot whales make up the genus Globicephala. The white-sided dolphin is classified as Lagenorhynchus obliquidens.
~ Encyclopedia Encarta
ROUGH-TOOTHED DOLPHIN
Body roughly cone-shaped in front of the flipper;beak long and slender, withno crease separating it from the forehead, as there is in most dolphins;body often covered with yellowish white blotches;lips and tip of snout white;eyes dark;distribution primarily pelagic, in tropical to warm temperate regions.
TUCUXI
Similar to Tursiops truncatus, except for smaller, nearly triangular dorsal fin, and tooth count, having 26-35 pairs in each jaw;limited to rivers and floooded jungles, as well as nearshore marine waters of northeastern South America and eastern Central America.
INDO-PACIFIC HUMP-BACKED DOLPHIN & ATLANTIC HUMP-BACKED DOLPHIN
Dorsal fin at midback consists of a long,ridged base surmounted by a small triangular of falcate fin-tip in adults,west of Indonesia;east of Indonesia the hump is lacking, but the fin is more pronounced;many animals have a speckled appearance;found in coastal waters of of West Africa and in Indo-Pacific;there appear to be two groups of undescribed relationshop in the Indo-Pacific,one west of Indonesia,one east and south of Indonesia.
WHITE-BEAKED DOLPHIN
Short,thick beak,white or light gray on European side of range, sometimes dark off North America;two white or gray areas on each side of body,one in front of,and the other behind and below,the dorsal fin;posterior light area continues onto dorsal aspect of caudal peduncle;limited to northern North Atlantic.
ATLANTIC WHITE-SIDED DOLPHIN
Narrow white patch on flanks;yellow or tan streak above white patch extending up toward ridge of tail;short,bicolored beak;limited to northern North Atlantic.
DUSKY DOLPHIN
Lack of a prominent beak;erect,slightly hooked,two-tone dorsal fin; a pair of gray"suspenders"along the back;two dark,shadowlike blazes at midflank pointing tailward;found in temperate southern hemishere.
PACIFIC WHITE-SIDED DOLPHIN
Short,thick beak,clearly demarcated from forehead;dorsal fin sharply hooked,usually dark on leading edge,lighter posteriorly;back dark,but with two stripes or"suspenders"from head to near tail;distribution limited to North Pacific.
HOURGLASS DOLPHIN
Sharply demarcated black-and-white coloration,with dorsal and ventrolateral dark zones meeting at midflank,separating white sides into anterior and posterior zones;found only in high latitudes of southern hemisphere.
PEALE'S DOLPHIN
Similar to L.obscurus,but coloration muted;black face and throat; conspicuous dark,diagonal flank patch,above which is a white patch narrowing anteriorly;small white patch above and behind flipper;found only in coastal waters of southern South America and in the vicinity of the Falkland Islands.
FRASER'S DOLPHIN
Short beak;relatively small flippers,flukes,and dorsal fin(subtriangular); wide,prominent eye-to-anus black band;stocky build;tropical distribution.
COMMON DOLPHIN
Conspicuous white thoracic patch;V-shaped black or dark-gray saddle with downward-oriented apex on sides directly below dorsal fin;light gray of flank sweeping over dorsal aspect of tail stock;hourglass effect on side, with tan or yellowish tan region making up posterior half of hourglass; absent from high latitudes,but otherwise cosmopolitan.
RISSO'S DOLPHIN
White or light-gray coloration of adults,usually interrupted only by dark dorsal fin,flippers,and flukes;tall,falcate dorsal fin;extensive scarring on adults;lack of beak;squaris melon bisected by deep crease;primarily found in deep tropiccal and warm temperate waters worldwide.
SPOTTED DOLPHIN
Body usually spotted,differing by region and age;spotting generally decreases with distance from continental shores of Notth America,but within populations increases with age;beak long and slim;distribution primarily tropical but includes some warm temperate waters in Atlantic; distribution primarily oceanic.
STRIPED DOLPHIN
Black lateral stripes from eye to flipper and eye to anus;white v-shaped "shoulder blaze,"originating above and behind the eye,and narrowing to a point below and behind the dorsal fin. Primarily tropical to warm temperate distribution.
LONG-SNOUTED SPINNER DOLPHIN (Stenella longirostris)& SHORT-SNOUTED SPINNER (or Clymene)DOLPHIN
Long,slim snout(longirostris only);lips and tio of snout dark;habitually jumping and spinning on longitudinal axis;dorsal fin usually tiangular or canted slightly forward,often with a light spot in center of dark area; tail stock of adult males usually strongly keeled;distribution tropical to warm temperate,primarily in deep water.
SOUTHERN RIGHT WHALE DOLPHIN
No dorsal fin;body slim and graceful;striking black and white coloration; white zones covering head and extending onto sides,including flippers,and onto tail stock;small but distinct beak;limited to temperate portions of the southern hemisphere.
NORTHERN RIGHT WHALE DOLPHIN
No dorsal fin;body slim and graceful;coloration visible in water primarily blck;small amounts of white ventral hourglass pattern visible around flippers;small but distinct beak;limited to temperate North Pacific.
BLACK DOLPHIN
Low, rounded dorsal fin;no beak;dark pigmentation;limited to the coastal waters of Chile.
PINK DOLPHINS
Pink Dolphins have the highest spiritual frequency.
Pink Dolphins can be found in the waters off Argentina.
This unique dolphin picture was taken in Hong Kong.
BOTTLENOSE DOLPHINS
The most common species of coastal dolphins in the Atlantic Ocean and Gulf of Mexico.
The elongated beak gives this name to the bottle-nosed dolphin They are solid gray above, and pale gray to white and pink below.
The bottlenose dolphin, whose scientific name is Tursiops truncatus, is probably the dolphin most familiar to the general population because of its adaptability of living in human care. Bottlenose dolphins can be seen in various show and research facilities and have been the "stars" of many movies and television shows. Because of their seeming curiosity about people and their close proximity to various shores and ocean bays, this species is the most studied of all delphinids. The bottlenose is the dolphin most often sighted off the coast and from small boats. In some places in the world, such as Monkey Mia in Australia, wild bottlenose dolphins choose to come into bays and interact with human beings.
Bottlenose dolphins are the largest of the beaked dolphins. There is a definite crease where the rostrum (snout or beak) joins the melon, and the shape of the mouth seems to form a permanent smile. Their bodies are dark gray on the back and sides, fading to a pinkish white belly underneath. Their dorsal fins are falcate, curving slightly to the back. Pectoral fins and flukes are pointed at the tips. Atlantic bottlenose dolphins are usually 6 to 9 feet long at maturity; the Pacific variety often may be larger.
The exact number of the world population of bottlenose dolphins is unknown. They are found world-wide and in many types of waters from coastal and inshore waters to the pelagic waters of the deep oceans, from warm tropical waters around the equator to the colder temperate regions. In general, bottlenose dolphins can be found in all coastal waters throughout the world, except for the polar seas.
In the Pacific Ocean, bottlenose dolphins range from northern Japan to southern Australia and New Zealand, and from southern California down the coast of Chile. Populations located in the inshore waters of New Guinea and northern Australia often share their range with the Indo-Pacific humpback dolphin, while offshore populations are often seen associating with pilot whales.
In the Atlantic Ocean, bottlenose may be found from Nova Scotia to Norway, extending south to Argentina and the southern tip of South Africa. In the west Atlantic, including both Hudson Bay and the Caribbean Sea, bottlenose dolphins are fairly widespread. Abundant populations are located in Florida's coastal waters and in the Gulf of Mexico. Less commonly, they may be found off the Virginia coast and in Chesapeake Bay. Many offshore populations in the Atlantic coexist with pods of pilot whales or other species. Although bottlenose dolphins were once commonly seen in the coastal waters of the northeast Atlantic, populations along the English Channel coasts seem to have declined. Some offshore groups can still be found, and others exist in bays and estuaries, particularly along the coast of western Ireland.
Bottlenose dolphins are also common throughout the Indian Ocean from the coasts of India and Sri Lanka to the southern tips of South Africa and New Zealand. Both inshore and deep water, pelagic populations are well known throughout this area, including the Mediterranean Sea, the Persian Gulf, and the Red and Black Seas. The bottlenose dolphin seems to be one of the most abundant species found in Israeli waters and along the Egyptian coast.
We are far from knowing the precise ranges of the various populations of bottlenose dolphins around the world, especially those who live far from shore. Most, however, seem to prefer a relatively small area within a protected bay or shallow lagoon. They seem to establish a "home base," but must often move within a larger range to find food, to mate, or to escape predators.
Scientists have found that small pods of bottlenose dolphins near San Diego, California seem to have a range of approximately 20 miles along the coastline. When Randy Wells studied bottlenose off Sarasota, Florida, he found that local populations had a range of about 85 square kilometers, with individuals defining smaller home ranges for themselves. He found that distances traveled varied by sex and age of the dolphins: females with calves seemed to have the largest home range (average 40 square km); juvenile males tended to establish a somewhat smaller one; adult male groups, adult females without calves, and juvenile females had the smallest ranges of approximately 15-20 square km. Each subrange of the larger pods was centered in different areas, possibly due to the fact that dolphin pods tend to be segregated by sex and age. Other studies in Argentina, Texas, and California had similar results and have promoted the theory that social units of like sex and age tend to define the home ranges of various pods.
Feeding Most Odontoceti (toothed whales) feed on various types of fish or squid, although the Orca also will prey upon birds and other marine mammals, often many times larger than itself. The various species of toothed whales have long rows of sharp teeth, suitable for grasping quick-moving prey such as fish and squid. They do not chew their food, but swallow it whole, using muscles at the back of their tongue and throat to squeeze the salt water out and the fish down. The preferred food of a particular species or stock depends on its physiological feeding apparatus, the ecology of the area in which it is located (water temperature, terrain, depth), and the feeding behaviors practiced by that group.
Diet may indirectly determine the size of a pod. For example, the largest toothed whale, the sperm whale, feeds on giant squid of over 12 meters in length which are found at great depths and do not occur in large numbers. Sperm whales may travel individually or with only one or two other whales to facilitate finding enough food. An average pod of pelagic dolphins that eat small squid usually numbers less than 100, depending on the concentration of squid in any particular area. The common, spinner and spotted dolphins feed on shoaling fish and may travel in pods numbering in the thousands.
The natural diet of the bottlenose dolphin seems to vary according to its home region. Open water pods tend to feed mostly on pelagic fish, such as blue whiting, cod fish, and squid. Those found in coastal Atlantic waters feed on mullet, herring, smelt, capelin, catfish, eels, shrimp, and other crustaceans. In the Indian Ocean, dolphins will be more likely to feed on coral reef dwelling fish and mullet. Haddock, anchovies, and mackerel also seem to be favorites of some populations.
Dolphins usually forage for food in groups. Because fish tend to be distributed throughout their range in ever-moving schools, they must search for their prey. If they remained in only one small area constantly, they would soon exhaust the available food supply; therefore, they tend to leave and then revisit various feeding grounds on a periodic basis. By hunting cooperatively in groups, dolphins can cover a wider area and combine their collective experience. Knowledge of topographical features of the area, as well as their ability to scan the area acoustically under water, contribute to their ability to find food. Most dolphins and fish- or squid-eating small whales travel in groups which are broader than they are long, enabling them to scan a wider area with their echolocation.
In the waters of South Africa, researchers have observed a single line of approximately 200 bottlenose dolphins traveling quickly and cooperatively in their search for food. Based on observations of behavior such as synchronous dives and recordings of vocalizations, scientists have theorized that pods of dolphins remain in constant acoustic contact while foraging.
Bottlenose dolphins seem to work together during feeding as well as while searching for fish. Researchers have observed them using a variety of cooperative methods to entrap their prey which reduce the amount of energy expended by any individual. Small groups may converge on a central point by porpoising to that point, and bunching fish up together in the center. Groups have been observed moving synchronously in a U-shaped formation towards other individuals, trapping the fish in between. At times, individuals may dive down and herd a school of fish upwards by swimming around and under them, tightening the circle until the fish are forced to the surface where the rest of the pod is waiting to feed.
Other, more unusual methods also have been noted by researchers. Dolphins have been observed using a sloping, sandy beach as a barrier while herding schools of fish. In some areas, dolphins will chase fish onto mudflats, then actually almost beach themselves by sliding out of the water to seize their prey. Scientists have theorized that some dolphins may use a burst pulse--a stream of very powerful sounds--to stun or confuse their prey.
On the west coast of Africa, bottlenose dolphins even work cooperatively with humans to ensure their food supply. The dolphins herd mullet to the shallows where native fishermen wait with gill nets to trap the fish. The fishermen allow the dolphins to eat their fill, then take the rest. The fishermen apparently can alert the dolphins to feeding time by slapping the water with sticks as a cue for food.
In southern Brazil, bottlenose dolphins have been the initiators of another fishing cooperative. A pod of dolphins alerts the men of Laguna to "feeding time" by stationing themselves offshore in a line. When a dolphin leaves the line, swims seaward, and returns, the men wait close to shore with their nets. When the dolphin reappears, comes to a full stop, and dives just out of net range, the fishermen closest to the dolphin cast their nets, even though the water is murky and they cannot see any fish. The cue given by the dolphins is reliable; few fishermen waste their time casting until instructed to do so by the dolphins' actions. After one or more men fill their nets, others come to take their place. If the dolphins move along the shore, the men will follow. The dolphins seem to take advantage of the confusion which results as the men cast their nets, feeding on their own from the remaining fish. Town records indicate that this partnership has lasted through several generations of both men and dolphins since 1847.
The scientific order 'Cetacea' is comprised of whales, dolphins, and porpoises. These aquatic creatures are the most specialized of all mammals, with adaptations that allow them to spend their entire lives in water. Living cetaceans are divided into two distinct suborders, Mysticeti and Odontoceti, which are divided further into a total of thirteen families. The Mysticeti suborder contains those whales, which have baleen plates instead of teeth. A baleen whale feeds by straining water through the baleen, trapping the fish, shrimp, crustaceans, or krill inside its mouth. This suborder is comprised of the largest whale species, including the blue whale, the humpback whale, and the grey whale.
Those cetaceans classified in the suborder Odontoceti are toothed whales, dolphins, and porpoises. They are generally smaller, faster, and more agile than their baleen counterparts. Scientists have identified approximately 80 species of toothed whales, ranging in size from the 60-foot sperm whale to the five-foot harbor porpoise. The various species are incredibly diverse and display a multitude of body shapes, behavior patterns, and lifestyles. Some spend barely any time on the surface, rising occasionally to take a breath; others can leap 20 feet out of the water almost effortlessly. Some species live in the shallows close to shore, some reside in deep oceans, and still others are found only in fresh water rivers. Odontoceti may have anywhere from eight to 250 teeth, and their eyesight ranges from poor to excellent.
Dolphins emit pulses of sound from the melon, a fatty area just below the blowhole. Much like the orientation vocalizations of a bat, these pulses, or clicks, return as echoes when the sound bounces off objects in the dolphin's path. The animal uses the echoes to navigate and to judge the distance to, and location of, prey as small as shrimp. Dolphins also produce whistling sounds when excited or communicating with other dolphins. These sounds arise from the larynx.
Dolphin (aquatic mammal), fast-swimming animal related to whales and porpoises. Sleek and powerful swimmers found in all seas, dolphins are distinguished from porpoises by well-defined, beaklike snouts and conical teeth. The porpoise has a blunt snout, chisel-shaped teeth, and a stouter body.
There are approximately 57 species of dolphins. Most have an elongated beak called a rostrum. The difference between porpoise and dolphin is in the shape of the teeth. Dolphins have cone shaped teeth whereas porpoise have spade shaped teeth. Most porpoise live in colder waters and are smaller than most dolphins, and they have no elongated beak.
The largest of all Dolphins is the Orca, or Killer Whale. It is the most powerful creature that lives in the oceans. It is the fiercest of sea predators and fears no other creature whatsoever.
Typical examples are the bottle-nosed dolphin, a popular performer in seaquariums, and the common dolphin, which inspired many Mediterranean folk legends. Both often appear in open waters, making their characteristic arched bounds, frequently before the bow waves of ships. Several freshwater species inhabit river estuaries in Asia and South America.
The small, graceful tucuxi dolphin has been sighted more than 2000 km (more than 1250 mi) up the Amazon River. The tucuxi, the smallest dolphin, is less than 1.2 m (less than 4 ft) long; the largest, the bottle-nosed dolphin, reaches a length of 3 m (10 ft). The killer whale is considered a dolphin despite its much greater length of 9 m (30 ft). The pilot whale is also considered a type of dolphin.
Dolphins once were hunted commercially, especially for the small quantity of valuable oil extracted from parts of the head and used to lubricate delicate watch mechanisms. Cheaper oils have now been found from other sources, and dolphins are no longer hunted for this reason. Many dolphins, however, become accidentally trapped and drowned in tuna nets; between 1959 and 1972 an estimated 4.8 million dolphins died in this way.
Under pressure from animal rights activists and United States consumers, both domestic and international tuna canners have refused to accept shipments from fishing fleets that do not protect dolphins. Concern has also been expressed about the treatment of dolphins on display in public aquariums and in ³swim with the dolphins² programs. The Marine Mammal Protection Act of 1972, amended in 1988 and 1992, was passed to prevent exploitation of dolphins and related aquatic animals. The National Marine Fisheries Service is the principal regulatory agency.
Behavior
In one day dolphins eat an amount of food, mostly fish and squid, equal to nearly one-third of their weight. Dolphins are swift enough to easily outdistance their prey. They seize their catches with jaws that have from 200 to 250 sharp teeth. Dolphins follow schools of fish in groups of varying size. Some species, such as the Pacific white-sided dolphin, make up aggregations estimated at tens of thousands of members. Less gregarious species, such as the bottle-nosed dolphin, join in groups that often contain only a few members.
Dolphins, like whales, breathe through a blowhole at the top of the head. As they travel they break surface about every two minutes to make a short, explosive exhalation, followed by a longer inhalation before submerging again. The tail, like that of other aquatic mammals, strokes in an up-and-down motion, with the double flukes driving the animal forward; the flippers are used for stabilization. Dolphins are superbly streamlined and can sustain speeds of up to 30 km/h (up to 19 mph), with bursts of more than 40 km/h (more than 25 mph). Their lungs, which are adapted to resist the physical problems created for many animals by rapid changes in pressure, enable them to dive to depths of more than 300 m (more than 1000 ft).
Adults of the bottle-nosed dolphin‹the best-studied species‹come to sexual maturity after 5 to 12 years in females and 9 to 13 years in males. They mate in the spring; after a gestation period of 11 or 12 months, a single calf is born, tail first. Calves swim and breathe minutes after birth; they nurse for up to 18 months. They are able to keep up with the mother by remaining close and taking advantage of the aerodynamic effects of the mother's swimming.
Vocalizations and IntelligencePrint section
Dolphins almost constantly emit either clicking sounds or whistles. The clicks are short pulses of about 300 sounds per second, emitted from a mechanism located just below the blowhole. These clicks are used for the echolocation of objects and are resonated forward by the so-called oily melon, which is located above the forehead and acts as an acoustic lens. Echoes received at the area of the rear of the lower jaw are transmitted by a fat organ in the lower jaw to the middle ear. This echolocation system, similar to that of a bat, enables the dolphin to navigate among its companions and larger objects and to detect fish, squid, and even small shrimp. The whistles are single-toned squeals that come from deeper in the larynx. They are used to communicate alarm, sexual excitement, and perhaps other emotional states.
Because of the ability of dolphins to learn and perform complex tasks in captivity, their continuous communications with one another, and their ability, through training, to approximate the sounds of a few human words, some investigators have suggested that the animals might be capable of learning a true language and communicating with humans. Most authorities, however, agree that although the dolphin's problem-solving abilities put the animal on an intelligence level close to that of primates, no evidence exists that dolphin communications approach the complexity of a true language.
The name dolphin is also applied to food fish of a different genus that have long, continuous dorsal fins. The fish, found worldwide in tropical marine waters, can reach a length of 1.5 m (5 ft).
Scientific classification: Dolphins belong to the suborder Odontoceti of the order Cetacea. The bottle-nosed dolphin is classified as Tursiops truncatus, the common dolphin as Delphinus delphis, and the tucuxi dolphin as Sotalia fluviatilis. The killer whale is classified as Orcinus orca. Pilot whales make up the genus Globicephala. The white-sided dolphin is classified as Lagenorhynchus obliquidens.
~ Encyclopedia Encarta
ROUGH-TOOTHED DOLPHIN
Body roughly cone-shaped in front of the flipper;beak long and slender, withno crease separating it from the forehead, as there is in most dolphins;body often covered with yellowish white blotches;lips and tip of snout white;eyes dark;distribution primarily pelagic, in tropical to warm temperate regions.
TUCUXI
Similar to Tursiops truncatus, except for smaller, nearly triangular dorsal fin, and tooth count, having 26-35 pairs in each jaw;limited to rivers and floooded jungles, as well as nearshore marine waters of northeastern South America and eastern Central America.
INDO-PACIFIC HUMP-BACKED DOLPHIN & ATLANTIC HUMP-BACKED DOLPHIN
Dorsal fin at midback consists of a long,ridged base surmounted by a small triangular of falcate fin-tip in adults,west of Indonesia;east of Indonesia the hump is lacking, but the fin is more pronounced;many animals have a speckled appearance;found in coastal waters of of West Africa and in Indo-Pacific;there appear to be two groups of undescribed relationshop in the Indo-Pacific,one west of Indonesia,one east and south of Indonesia.
WHITE-BEAKED DOLPHIN
Short,thick beak,white or light gray on European side of range, sometimes dark off North America;two white or gray areas on each side of body,one in front of,and the other behind and below,the dorsal fin;posterior light area continues onto dorsal aspect of caudal peduncle;limited to northern North Atlantic.
ATLANTIC WHITE-SIDED DOLPHIN
Narrow white patch on flanks;yellow or tan streak above white patch extending up toward ridge of tail;short,bicolored beak;limited to northern North Atlantic.
DUSKY DOLPHIN
Lack of a prominent beak;erect,slightly hooked,two-tone dorsal fin; a pair of gray"suspenders"along the back;two dark,shadowlike blazes at midflank pointing tailward;found in temperate southern hemishere.
PACIFIC WHITE-SIDED DOLPHIN
Short,thick beak,clearly demarcated from forehead;dorsal fin sharply hooked,usually dark on leading edge,lighter posteriorly;back dark,but with two stripes or"suspenders"from head to near tail;distribution limited to North Pacific.
HOURGLASS DOLPHIN
Sharply demarcated black-and-white coloration,with dorsal and ventrolateral dark zones meeting at midflank,separating white sides into anterior and posterior zones;found only in high latitudes of southern hemisphere.
PEALE'S DOLPHIN
Similar to L.obscurus,but coloration muted;black face and throat; conspicuous dark,diagonal flank patch,above which is a white patch narrowing anteriorly;small white patch above and behind flipper;found only in coastal waters of southern South America and in the vicinity of the Falkland Islands.
FRASER'S DOLPHIN
Short beak;relatively small flippers,flukes,and dorsal fin(subtriangular); wide,prominent eye-to-anus black band;stocky build;tropical distribution.
COMMON DOLPHIN
Conspicuous white thoracic patch;V-shaped black or dark-gray saddle with downward-oriented apex on sides directly below dorsal fin;light gray of flank sweeping over dorsal aspect of tail stock;hourglass effect on side, with tan or yellowish tan region making up posterior half of hourglass; absent from high latitudes,but otherwise cosmopolitan.
RISSO'S DOLPHIN
White or light-gray coloration of adults,usually interrupted only by dark dorsal fin,flippers,and flukes;tall,falcate dorsal fin;extensive scarring on adults;lack of beak;squaris melon bisected by deep crease;primarily found in deep tropiccal and warm temperate waters worldwide.
SPOTTED DOLPHIN
Body usually spotted,differing by region and age;spotting generally decreases with distance from continental shores of Notth America,but within populations increases with age;beak long and slim;distribution primarily tropical but includes some warm temperate waters in Atlantic; distribution primarily oceanic.
STRIPED DOLPHIN
Black lateral stripes from eye to flipper and eye to anus;white v-shaped "shoulder blaze,"originating above and behind the eye,and narrowing to a point below and behind the dorsal fin. Primarily tropical to warm temperate distribution.
LONG-SNOUTED SPINNER DOLPHIN (Stenella longirostris)& SHORT-SNOUTED SPINNER (or Clymene)DOLPHIN
Long,slim snout(longirostris only);lips and tio of snout dark;habitually jumping and spinning on longitudinal axis;dorsal fin usually tiangular or canted slightly forward,often with a light spot in center of dark area; tail stock of adult males usually strongly keeled;distribution tropical to warm temperate,primarily in deep water.
SOUTHERN RIGHT WHALE DOLPHIN
No dorsal fin;body slim and graceful;striking black and white coloration; white zones covering head and extending onto sides,including flippers,and onto tail stock;small but distinct beak;limited to temperate portions of the southern hemisphere.
NORTHERN RIGHT WHALE DOLPHIN
No dorsal fin;body slim and graceful;coloration visible in water primarily blck;small amounts of white ventral hourglass pattern visible around flippers;small but distinct beak;limited to temperate North Pacific.
BLACK DOLPHIN
Low, rounded dorsal fin;no beak;dark pigmentation;limited to the coastal waters of Chile.
PINK DOLPHINS
Pink Dolphins have the highest spiritual frequency.
Pink Dolphins can be found in the waters off Argentina.
This unique dolphin picture was taken in Hong Kong.
BOTTLENOSE DOLPHINS
The most common species of coastal dolphins in the Atlantic Ocean and Gulf of Mexico.
The elongated beak gives this name to the bottle-nosed dolphin They are solid gray above, and pale gray to white and pink below.
The bottlenose dolphin, whose scientific name is Tursiops truncatus, is probably the dolphin most familiar to the general population because of its adaptability of living in human care. Bottlenose dolphins can be seen in various show and research facilities and have been the "stars" of many movies and television shows. Because of their seeming curiosity about people and their close proximity to various shores and ocean bays, this species is the most studied of all delphinids. The bottlenose is the dolphin most often sighted off the coast and from small boats. In some places in the world, such as Monkey Mia in Australia, wild bottlenose dolphins choose to come into bays and interact with human beings.
Bottlenose dolphins are the largest of the beaked dolphins. There is a definite crease where the rostrum (snout or beak) joins the melon, and the shape of the mouth seems to form a permanent smile. Their bodies are dark gray on the back and sides, fading to a pinkish white belly underneath. Their dorsal fins are falcate, curving slightly to the back. Pectoral fins and flukes are pointed at the tips. Atlantic bottlenose dolphins are usually 6 to 9 feet long at maturity; the Pacific variety often may be larger.
The exact number of the world population of bottlenose dolphins is unknown. They are found world-wide and in many types of waters from coastal and inshore waters to the pelagic waters of the deep oceans, from warm tropical waters around the equator to the colder temperate regions. In general, bottlenose dolphins can be found in all coastal waters throughout the world, except for the polar seas.
In the Pacific Ocean, bottlenose dolphins range from northern Japan to southern Australia and New Zealand, and from southern California down the coast of Chile. Populations located in the inshore waters of New Guinea and northern Australia often share their range with the Indo-Pacific humpback dolphin, while offshore populations are often seen associating with pilot whales.
In the Atlantic Ocean, bottlenose may be found from Nova Scotia to Norway, extending south to Argentina and the southern tip of South Africa. In the west Atlantic, including both Hudson Bay and the Caribbean Sea, bottlenose dolphins are fairly widespread. Abundant populations are located in Florida's coastal waters and in the Gulf of Mexico. Less commonly, they may be found off the Virginia coast and in Chesapeake Bay. Many offshore populations in the Atlantic coexist with pods of pilot whales or other species. Although bottlenose dolphins were once commonly seen in the coastal waters of the northeast Atlantic, populations along the English Channel coasts seem to have declined. Some offshore groups can still be found, and others exist in bays and estuaries, particularly along the coast of western Ireland.
Bottlenose dolphins are also common throughout the Indian Ocean from the coasts of India and Sri Lanka to the southern tips of South Africa and New Zealand. Both inshore and deep water, pelagic populations are well known throughout this area, including the Mediterranean Sea, the Persian Gulf, and the Red and Black Seas. The bottlenose dolphin seems to be one of the most abundant species found in Israeli waters and along the Egyptian coast.
We are far from knowing the precise ranges of the various populations of bottlenose dolphins around the world, especially those who live far from shore. Most, however, seem to prefer a relatively small area within a protected bay or shallow lagoon. They seem to establish a "home base," but must often move within a larger range to find food, to mate, or to escape predators.
Scientists have found that small pods of bottlenose dolphins near San Diego, California seem to have a range of approximately 20 miles along the coastline. When Randy Wells studied bottlenose off Sarasota, Florida, he found that local populations had a range of about 85 square kilometers, with individuals defining smaller home ranges for themselves. He found that distances traveled varied by sex and age of the dolphins: females with calves seemed to have the largest home range (average 40 square km); juvenile males tended to establish a somewhat smaller one; adult male groups, adult females without calves, and juvenile females had the smallest ranges of approximately 15-20 square km. Each subrange of the larger pods was centered in different areas, possibly due to the fact that dolphin pods tend to be segregated by sex and age. Other studies in Argentina, Texas, and California had similar results and have promoted the theory that social units of like sex and age tend to define the home ranges of various pods.
Feeding Most Odontoceti (toothed whales) feed on various types of fish or squid, although the Orca also will prey upon birds and other marine mammals, often many times larger than itself. The various species of toothed whales have long rows of sharp teeth, suitable for grasping quick-moving prey such as fish and squid. They do not chew their food, but swallow it whole, using muscles at the back of their tongue and throat to squeeze the salt water out and the fish down. The preferred food of a particular species or stock depends on its physiological feeding apparatus, the ecology of the area in which it is located (water temperature, terrain, depth), and the feeding behaviors practiced by that group.
Diet may indirectly determine the size of a pod. For example, the largest toothed whale, the sperm whale, feeds on giant squid of over 12 meters in length which are found at great depths and do not occur in large numbers. Sperm whales may travel individually or with only one or two other whales to facilitate finding enough food. An average pod of pelagic dolphins that eat small squid usually numbers less than 100, depending on the concentration of squid in any particular area. The common, spinner and spotted dolphins feed on shoaling fish and may travel in pods numbering in the thousands.
The natural diet of the bottlenose dolphin seems to vary according to its home region. Open water pods tend to feed mostly on pelagic fish, such as blue whiting, cod fish, and squid. Those found in coastal Atlantic waters feed on mullet, herring, smelt, capelin, catfish, eels, shrimp, and other crustaceans. In the Indian Ocean, dolphins will be more likely to feed on coral reef dwelling fish and mullet. Haddock, anchovies, and mackerel also seem to be favorites of some populations.
Dolphins usually forage for food in groups. Because fish tend to be distributed throughout their range in ever-moving schools, they must search for their prey. If they remained in only one small area constantly, they would soon exhaust the available food supply; therefore, they tend to leave and then revisit various feeding grounds on a periodic basis. By hunting cooperatively in groups, dolphins can cover a wider area and combine their collective experience. Knowledge of topographical features of the area, as well as their ability to scan the area acoustically under water, contribute to their ability to find food. Most dolphins and fish- or squid-eating small whales travel in groups which are broader than they are long, enabling them to scan a wider area with their echolocation.
In the waters of South Africa, researchers have observed a single line of approximately 200 bottlenose dolphins traveling quickly and cooperatively in their search for food. Based on observations of behavior such as synchronous dives and recordings of vocalizations, scientists have theorized that pods of dolphins remain in constant acoustic contact while foraging.
Bottlenose dolphins seem to work together during feeding as well as while searching for fish. Researchers have observed them using a variety of cooperative methods to entrap their prey which reduce the amount of energy expended by any individual. Small groups may converge on a central point by porpoising to that point, and bunching fish up together in the center. Groups have been observed moving synchronously in a U-shaped formation towards other individuals, trapping the fish in between. At times, individuals may dive down and herd a school of fish upwards by swimming around and under them, tightening the circle until the fish are forced to the surface where the rest of the pod is waiting to feed.
Other, more unusual methods also have been noted by researchers. Dolphins have been observed using a sloping, sandy beach as a barrier while herding schools of fish. In some areas, dolphins will chase fish onto mudflats, then actually almost beach themselves by sliding out of the water to seize their prey. Scientists have theorized that some dolphins may use a burst pulse--a stream of very powerful sounds--to stun or confuse their prey.
On the west coast of Africa, bottlenose dolphins even work cooperatively with humans to ensure their food supply. The dolphins herd mullet to the shallows where native fishermen wait with gill nets to trap the fish. The fishermen allow the dolphins to eat their fill, then take the rest. The fishermen apparently can alert the dolphins to feeding time by slapping the water with sticks as a cue for food.
In southern Brazil, bottlenose dolphins have been the initiators of another fishing cooperative. A pod of dolphins alerts the men of Laguna to "feeding time" by stationing themselves offshore in a line. When a dolphin leaves the line, swims seaward, and returns, the men wait close to shore with their nets. When the dolphin reappears, comes to a full stop, and dives just out of net range, the fishermen closest to the dolphin cast their nets, even though the water is murky and they cannot see any fish. The cue given by the dolphins is reliable; few fishermen waste their time casting until instructed to do so by the dolphins' actions. After one or more men fill their nets, others come to take their place. If the dolphins move along the shore, the men will follow. The dolphins seem to take advantage of the confusion which results as the men cast their nets, feeding on their own from the remaining fish. Town records indicate that this partnership has lasted through several generations of both men and dolphins since 1847.
Social Structure and Behaviors
Dolphins tend to be very social animals, swimming in social groupings called pods. These groups, however, are very flexible and fluid, not at all like the social unit we refer to as a family. Dr. Deborah Duffield has determined by observing pods of wild bottlenose dolphins that the majority of pod members are not closely related. They seem to be in a periodic state of flux; an individual dolphin traveling with one group may be swimming miles away with another by the next day. A more stable subgroup of two to six dolphins may remain together over long periods. Mothers and their calves have been observed together for at least three to six years, and unrelated adults often form long-term bonds, usually within the same sex and age group.
Separation by age and sex is common. Breeding groups are usually composed of mothers and their calves. As the youngsters begin to mature, they may branch off into a juvenile pod. Mature males will rarely be seen mixing with a maternity pod or a juvenile pod. The fluidity of the groups, however, allows increased opportunities for mating, enabling males to court a wider variety of females. During feeding, smaller pods may interact and join into larger groups. Bottlenose dolphins also have been observed swimming and feeding with other cetaceans such as sperm whales, gray whales, humpbacked dolphins, and right whales.
Although solitary individuals are sometimes seen in the wild, bottlenose dolphins usually live in pods composed of two to twenty-five dolphins. Inshore groups tend to be smaller, with an average size of ten, but groupings may exist as large as one thousand. The size of the group may depend partially on the need for surveillance against predators, as well as the quantity and distribution of available food.
Dolphins seem to acknowledge a hierarchy within each pod. Status may be expressed by positioning, formation of subgroups within the pod, or by feeding order. Behaviors, such as teeth raking, tail slapping, jaw popping, biting, or ramming may also express dominance.
Sri Lanka peace mixed blessing for war-torn beaches By Dayan Candappa
TRINCOMALEE, Sri Lanka (Reuters) - V. Premkumar once longed for the day when peace would pack the sands of his battle-scarred Sri Lankan beach resort with tourists.
Now, with a Norwegian-brokered truce in place and talks to end the ethnic conflict around the corner, he is not so sure.
Premkumar is the manager of the Nilaweli resort near the port of Trincomalee -- one of a string of bewitchingly beautiful beaches that are among the island's best-kept secrets thanks to nearly two decades of war waged by Tamil separatists.
Premkumar fears peace will open the pristine northeastern coast to the low-budget, mass-market tourism that has scarred beaches elsewhere in Sri Lanka.
"Of course I want peace and tourism like everyone else. But unless the authorities make sure this doesn't end up like the other resorts we won't have any tourists," said Premkumar.
His concerns are shared by environmentalists and the handful of die-hard eco-tourists willing to pay for east coast resorts despite a conflict that has killed more than 64,000 people.
"We need to save this place from package tourists," said German accountant Hans Heise.
Heise and his family are regular visitors to Sri Lanka and spend much of their time with the rest of the island's 400,000 tourists in the resorts of southwest coast.
But this year his son threatened to boycott the family vacation unless it included a trip to Trincomalee, about 240 km (150 miles) northeast of the capital Colombo.
It is not hard to see why. The emerald expanse of Trincomalee bay is ringed with mile upon gleaming mile of beach.
TOURIST EL DORADO
Unlike the slivers of sand squeezed between resorts in the south, Trincomalee's beaches are enormous, starting under the shadows of scrub jungles and sloping so gently into the ocean that the water is only chest deep 100 m (330 ft) from the shore.
This is El Dorado for a tourist industry that has never shaken off the war's shadow, despite crippling price cuts and ruthless development of the less enchanting but safe southwest coast.
The tourist board has now begun an eco-tourism drive to woo back high-spending Westerners from the Maldives, a coral island nation a one-hour flight from Colombo on the west coast.
"We must make sure that don't fall into the same trap that prevents sensible, sustainable tourism," said Gehan De Silva Wijeratne, director of Jetwing Eco-Holidays.
The road to Nilaweli is free of the cheap bars and pricey boutiques that cram other tourist towns, though troupes of monkeys can be as pesky as touts and views of rice paddies are interrupted by the occasional barracks or bombed-out house.
DANCING DOLPHINS
A 15-minute boat ride to Pigeon Island reveals coral reefs as yet unmolested by trophy hunters, and snorkellers surface to gasp air that has not the slightest whiff of diesel.
Out in Trincomalee bay, flying fish flop on to boats, gregarious dolphins dance to the throb of the engines and the lucky few may glimpse the dark flukes of a diving blue whale.
"This is the paradise portrayed on the cover of every tourist brochure," said Frenchman Boiton Robert.
Trincomalee's status as the capital designate of the separate minority Tamil state demanded by the rebel Liberation Tigers of Tamil Eelam has kept it out of tourist brochures for years.
But Premkumar's Nilaweli beach hotel, now packed because of a lull in the fighting, has often had enough guests to stay open, while surfing fanatics have always flocked to waves of Arugam Bay at the southernmost tip of the war zone further down the coast.
But most resorts have been less fortunate. The Norwegian-brokered truce signed in February has not broken the eerie silence surrounding Pasikudah, arguably the island's most beautiful beach, 70 km (43 miles) south of Trincomalee.
The palm-sheltered cove cut off from the ocean by great scallops of pink coral has not seen a tourist in years.
More than a dozen hotels competed for Pasikudah's beach front during a tourist boom before all-out war erupted in 1983. Now weeds push through the bottoms of dry swimming pools and hermit crabs burrow under restaurants levelled by the fighting.
But many Sri Lankans may be willing to brave the battle zone to revive livelihoods shattered by the war and almost destroyed last year by a rebel attack on the country's only international airport.
"There are only a few boats in Trincomalee," said one tour boat operator, who left the south a few months ago, speaking on condition of anonymity.
"One ride here brings more money than three in the south".
(Yahoo! India News:Sunday April 14, 8:40 AM)
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