Facts about Sea Lions

Sea lions are one of the largest marine mammals that double up as amphibians, i.e., they are equally capable on land, as they are under water. These beautiful (though less than graceful) sea creatures are fast disappearing from earth, causes of which are still under study. Their inexplicable disappearance has made conversationalists work overtime to find ways to increase their numbers and get them off the endangered animals list.

Sea lions may be bulky and overweight, less flattering and attractive and relatively unknown to the masses, but they form an essential link in the food chain of our ecosystem. Listed below are some facts on them:

Territory and Location
One foolproof way to escape a sea lion is not to mess with him in the first place. In order to not mess with him, you need a chart. A chart?! Yes, a chart of their territories, for boy, are these animals territorial! I may have got it wrong, completely wrong, there. It should be territorial with a capital 't'. Their population can be divided in two parts: the Eastern population (California, British Columbia and South Eastern Alaska) and the Western population (Gulf of Alaska, Bering Sea, Russia and Japan). Their territories range far and wide in both the hemispheres and in all waters except the Atlantic ocean.

Science
Sea lions, commonly known as the 'Stellar sea lions', are scientifically known as 'Eumetopias Jubatus'. They form a part of the 'Otaridae' family which is a collective grouping of what are known as 'eared seals'.The genre of sea lions includes any of their 7 species listed under the group of 'modern pinnipeds'. Pinnipeds are mammals with external ear flaps and long front flippers. Sea lions are amphibious and are at equal ease both in the water and on land. Some awesome facts about them are that they can dive to the depths of around 1000 feet despite their bulk. They can also hold their breaths under water for 10 to 20 minutes as they have the ability to slow their heart rates whenever needed. They can swim at a speed of about 11 to 24 meters an hour and gallop on land at 25 to 30 kmph. Be careful, watch out for a stampede!

Physical Attributes
Sea lions are oddly designed. They look rather inelegant walking on land on their four flippers. Their bodies are however, perfectly streamlined for movement in dense waters. They have a short, coarse fur coat that looks yellowish-brown when dry. The males and females weigh 907 kg (2000 lbs) and 272 kg (600 lbs) respectively, on an average. These marine mammals can grow to about 7 to 10 feet in length. Under zoological conditions their life spans extend to 20 - 30 years but in the wild they only survive to about 10 or 15 years.

Food
The main diet of sea lions consists of various fish and cephalopods. These opportunistic predators will feed on anything convenient. They prey on squid, octopus, fish, seals, sharks and pups of other mammals. Their diet varies according to geographical region as well as seasonal change. Sea lions are voracious feeders and sometimes even eat their own young.

Social Life and Reproduction Cycles
Every year in spring, sea lions gather in large numbers at their breeding sites, also known as rookeries. Here, the females (which arrive later than the males) are herded into male territory by pre-appointed sea lions. Harems of about 15 or more females are thus formed and it is here that they give birth to one offspring (that was conceived during the last cycle). Mating begins soon after the birth of a pup, as conception for the next year's cycle starts. Gestation period lasts up to 10 to 11 months. Females produce just one pup each year and start reproducing at 4 - 6 years of age.

Pups remain with their mothers for about a year after which the 'yearlings' form playgroups for mock battles and play. The pups are initially black in color but molt their coats to light brown ones by the end of their second year. Male pups mature between 3 to 8 years but are unable to hold territory until they are 10 years old. While the others return to the rookeries each year, male pups do not return until they are 2 years old. Even then, these bachelors are isolated till they are large enough to compete for their territories. Male sea lions are polygamous.

Sea lion rookeries are specially chosen congregation places. They are chosen taking into account factors like food proximity, predator protection, topography, surf conditions, etc. Their rookeries are normally unhygienic and stinky as females rarely go underwater for defecation. Infestation by parasites could be a reason for high pup mortality.

Threats
The biggest threat for sea lions is reduction in their habitat. Their natural foods are also on a decline. Japan, for example, has given permission for 116 sea lion kills per year as they are a threat to commercial fisheries. Their natural predators - killer whales, sharks, polar bears, coyotes and wolves, are also responsible for a fall in their numbers. A major chunk of blame though, goes to man. Plastic pollution, oil spills, fishing nets, etc are more of a threat to them, than what we'd even like to consider. Apart from these, there is always disease and environmental change.

If nothing is done soon, our children might never know about them. They will fade away in time like the dodo and the already extinct Japanese sea lion. We can wake up now while there is still time. A first thing anyone who cares can do is to do away with sea lion fur accessories, sea lion meat and sea lion oils. Come on, is it not just a small price to pay to save a whole breed of these giants?