Sea lions are strong swimmers can reach speeds of nearly 20 miles per hour in the water. They swim using their long foreflippers to generate power and their hind flippers to steer. Sea lions hunt underwater and can dive to depths of meters. No, sea lions cannot breathe underwater.
However, they can hold their breath for approximately 8 to 20 minutes! Although they can dive to extraordinary depths, sea lions cannot breathe underwater. As they are mammals, sea lions must breathe air in order to survive.
However, sea lions have special physiological builds that allow them to conserve oxygen while diving. They can hold their breath for as long as 20 minutes approximately! On land, sea lions breathe through their nostrils.
Their nostrils instinctively shut when they dive underwater. Sea lions' nostrils are naturally closed when they are relaxing. They have special muscles that open the nostrils when they need to breathe. When sea lions are swimming underwater, their nostrils remain closed. The average lifespan for sea lions in the wild is 20 years. Various big cats like tigers, leopards, jaguars, lions, and ocelots are famous for cooling off in watering holes and their swimming skills are top-notch.
They seem to truly enjoy being in the water! The sea lion is the only water animal to swim this way. Most swimmers range from tuna to sea lion cousins, the squirrel pushing against the back of their bodies, using their tails to propel them into the water.
The fish they receive are flash-frozen from the north Atlantic and lose nutrients during the freezing process. Being in and out of the water makes sea lions susceptible to a variety of internal parasites. This is also a concern for wild sea lions. Great white, hammerhead and blue sharks, as well as killer whales, occasionally hunt sea lions. Young sea lions are often vulnerable to predation due to unfamiliarity with their new water environment.
Water pollution, as well as marine debris such as fishing line, also endangers our friends of the sea. Ropes can tangle around the necks of marine mammals and cut into their skin, blocking the passage for food and eventually resulting in starvation. During the late s and early s, sea lions were hunted and harvested for their blubber and fur.
Sea lions are now protected under the Marine Mammal Protection Act of Once a sea lion becomes sexually mature, at around age four or five, they are able to breed. Female sea lions are called cows, while males are called bulls. Those who live in Baja, California and southern California establish breeding territories from May through July.
Cows congregate in closely packed, moderate to large groups. Bulls defend territories and fast during the breeding season. Males compete for dominance, leaving the younger males without a chance to mate for the season.
One distinct characteristic of a full-grown breeding male is the presence of a sagittal crest, a raised forehead that appears at about 10 years of age. The dominant male will mate with an average of 16 females in one season. Once the egg is fertilized inside the female, she can delay implantation of the egg to stop the embryo from growing.
The delayed implantation may last up to three months with an average gestation period lasting 9 months. Sea lions mate approximately 20 - 30 days after the birth of their pup, leaving only about one month out of the entire year that she is not pregnant. In the Northern Hemisphere, pups tend to be born in mid-June. Each mother usually gives birth to a single pup. Twins are rare and mothers seldom adopt other pups. The pup nurses from the mother's four abdominal teats for about 6 - 12 months.
The length of lactation increases with the increasing age of the female. Pups begin feeding on fish along with the mother's milk after about two months. Between nursings the mother returns to the sea and feeds for several days, leaving her pup on the mainland. Once the mating season is over, the males seasonally migrate long distances north while the females do not move beyond the Southern California Channel Islands. The males return to the breeding grounds from March to May.
Available in English, Spanish, and Portugese. Bonner, W. The Natural History of Seals. Fay, Francis H. North American Fauna Wahington, D. Department of the Interior, Fish and Wildlife Service. Gentry, Roger L. Goodridge, Harry, and Lew Dietz. A Seal Called Andre. Down East Books, Camden, E. Hanggi, Evelyn B. Harrison, R. Hubbard, Richard S. Peterson, Charles E. Rice, and Ronald J. Schusterman, eds. The Behavior and Physiology of Pinnipeds. Meredith Corp. Leon, Vicki. Blake Publishing, Inc. King, Judith E.
Seals of the World. Second edition. Patent, Dorthy Hinshaw. Seals, Sea Lions and Walruses. Peterson, Richard S. Reeves, Randall R. Stewart, and Stephen Leathwood. Renouf, Deane, ed. The Behavior of Pinnipeds. Ridgway, Sam H. Harrison F. Handbook of Marine Mammals. Volume 2: Seals. Riedman, Marianne. Scheffer, Victor B. Stanford University Press, Stanford.
Stewart, B. Stuart, Frank S. Pyramid Publications, Inc. Book a Program. Help DRC. Donate Now. Gift Memberships. Clapping and gliding, rolling and twisting, sea lions can be hard to follow with the eye, much less explain with science. Figuring out this puzzle could be the secret to helping humans build stealthier autonomous submarines or other underwater vehicles, as WIRED magazine reported in In the meantime, remember to keep a healthy distance from any sea lion you happen to see, or you might be in for an unwelcome surprise.
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