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Khaleel 2008

Created By: Denim Wilson
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http://www.dolphinworld.org/stories/dolphins-diet-story.htm

[1]The majesty of the dolphin is only perpetuated by its stupendous beauty and grace, but what sustains these marvelous creatures? What do their diets really comprise of? Those in the field and marine biologists around the world seem to agree that dolphins eat a wide variety of different foods. Some of them eat fish, such as mackerel, herring and cod, while others eat squid. Large dolphins, such as Orcas may eat other marine mammals, such as sea lions or sea turtles. How much a dolphin eats depends a lot on what type of fish or squid they eat. Some fish, such as mackerel or herring, have a lot of fat in them. This means that a Dolphin will get a lot of energy from eating these fish. However, squid does not have much fat, so a Dolphin has to eat more squid to get the same kind of energy it would get from fish. On average, however, a 250 kg dolphin will typically eat between 10 kg and 22.5 kg of fish every day.

[2]The methods that these dolphins use to hunt for their food are astounding and simply ingenious. There are many different types of methods such as, herding, whacking, stunning, corralling, and foraging. We will go in depth and analyze each of these tactics because each is used in a different circumstance and ultimately a different situation. Method one, also known as herding, is one of the most common used by the basic dolphin, dolphins ally themselves with one another for the common good, and surround a of school of fish, and then take turns swimming through the densely packed school and eating their fill, until they are all filled, or will find another and repeat the process.

[3]Another type of method used to hunt by certain dolphins is commonly referred to as whacking; this is where dolphins strike the fish with their tales repeatedly in an effort to stun the fish into submission and then eating it. This generally refers to larger prey where brute force is required to put the fish into shock, or to knock it unconscious, in most cases the tale blow is not sufficient to completely kill the fish, but the dolphins by that time have already eaten the fish to solve that small problem.
One interesting method used by the dolphins is known as stunning. This is where the dolphin emits a high frequency acoustic missile in the form of a loud click noise, to stun the fish, and allow the dolphin enough time to eat the fish completely, this method when first discovered was astounding to marine biologists because it proved the intelligence of these creatures to access all parts of their arsenals, apart from their physical abilities and limitations.

Another type of method, corralling, is where the dolphin will sometimes herd a school of fish into a coral reef, making it hard for the fish to escape due to the reef behind it and the dolphin in front of it. This method can happen anywhere where coral reefs are present, but especially takes place along the great banks of Sydney, where the Great coral reef lies, and the opportunity to trap fishes are much higher than in normal waters.
Finally, one of the simplest yet amazingly efficient methods of hunting by the dolphins is known as foraging. This is where dolphins will pick up a sponge, and use it to push through the mud on the bottom of shallow parts of the ocean, looking for food. This seems to be the least common method used, but results have shown that statistically it does have a high yield return rate, as the ocean bed hides many different life forms that are easily consumed by the swimming dolphin.
All in all the diets of these creatures will range widely on the specific type of dolphin that is being analyzed, anywhere from mackerel to squid, and everything in between, like humans their diet is wide and varied, and like us their moods will determine what foods they might attempt to seek out more than the other, however unlike us while our meals are guaranteed on a daily basis, their meals have to be sought out and fought for which makes the majority of the dolphins more inclined to eat anything that is easiest to catch and most common in their area. Yet even more amazingly are these creatures varied abilities to utilize their skills in a method that makes catching their prey very effective.
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