The narwhal, a medium-sized whale with a long tooth that looks like a unicorn's horn, feeds on fish that swim in Arctic seas such as Greenland halibut, arctic cod, polar cod, squid, shrimp and cuttlefish. Because narwhals do not have well-developed teeth, they swim close to their prey and suck it into their mouths.Know More
Narwhals feed in deep Arctic waters often covered in sea ice, and for this reason it has been difficult to observe them feeding. Information on narwhal feeding habits has been obtained from examining their stomach contents. From these, it has been determined that they follow a very restricted and specific diet of only a few species of fish. Unlike most sub-arctic whales, narwhals feed mostly in winter. During the ice-free months of summer their stomachs are nearly empty. To feed, they make long, deep dives of up to 25 minutes into the total darkness at depths up to 4,500 feet. Physiological adaptations such as a compressible rib cage and the ability to carry a large amount of oxygen in their lungs, muscles and blood enable them to make the dives.
In medieval times, narwhal tusks were more valuable than gold, as they were believed to be unicorn horns. People attributed magical powers to them. In fact, the narwhal tusk is a front tooth that grows right through the narwhal's lip up to about 9 feet in length. Usually only males have tusks, and if females grow them, they are not as long as those of the males. Scientists have speculated about the purpose of the tusks, but the most prominent belief is that they have something to do with narwhal mating rituals.Learn more about Marine Life
Seahorses occupy a middle position in their food chain. They are carnivores that feed on tiny crustaceans, such as shrimp. The shrimp feed on algae, which are near the base of the food chain. Seahorses are preyed upon by crabs and fish, which are eaten by larger fish. These large fish are hunted by apex predators, including sharks that are at the top of the food chain.Full Answer >
Cnidarians obtain food, mostly prey animals such as crustaceans and fish, by passively waiting for animals to pass by and touch their tentacles, whereupon they poison them and draw them toward their mouths to be digested. One important exception to this pattern is corals, which instead have a mutualistic relationship with algae which generate food for them via photosynthesis. Cnidarians obtain food very passively, but also have low food requirements.Full Answer >
The most common techniques dolphins use to get food are called herding and corraling. Dolphins work together as a team to hunt and catch a school of fish and other prey.Full Answer >
Beluga whales live near the top of the food chain in the Arctic ocean. Belugas, also called white whales because of their white skin, eat small species of fish and crustaceans, such as salmon, smelt, herring, Arctic and polar cod, shrimp, crabs, mollusks and marine worms. Belugas, in turn, are preyed upon by killer whales, polar bears and humans.Full Answer >