Name - Sea lion
Scientific Name : Otariinae
Type : Aquatic Animal
Age : 20 – 30 years
Diet : Carnivore
Length : 1.4 m To 2.1 m.
Weight : 39 Kg. To 190 Kg.
Top Speed : 97 km/h
Colour : dark brown to black in color
Skin Type : fur but have hairs as well
Lifespan : 20 – 30 years
Current Population : 238,000
Current Population Trend : decreasing
Native : Northern Pacific between Asia and North America and off the coasts of South America, Antarctica, southwestern Africa and southern Australia with the Galápagos area as well.
Main Prey : Seals , Sea Lions , Dolphins
Habitat : subarctic to tropical waters of the global ocean exception of the northern Atlantic Ocean
Predators : different fish, including anchovies, herring salmon, sardines, krill and penguins
Lifestyle : Diurnal
Favourite Food : fish
· On the Islands, sea lions congregate in huge colonies on rocks and sandy beaches. They enter the water to eat and cool off when necessary.
· The physiology of sea lions is made up of several different components, and these processes regulate various aspects of their behaviour. Thermoregulation, osmoregulation, reproduction, metabolic rate, and many other aspects of sea lion ecology, including their ability to dive to great depths, are all dictated by physiology.
· The bodies of sea lions regulate heart rate, gas exchange, digestion rate, and blood flow, allowing them to dive for long periods of time while avoiding the negative effects of high pressure at depth.
· Deep dives’ high pressures allow gases like nitrogen to build up in tissues, which are then released upon surfacing, potentially resulting in death. Limiting the amount of gas exchange that happens while diving is one of the ways sea lions cope with the intense pressures.
· The increasing water pressure causes the alveoli to be compressed, pushing surface air into a cartilage-lined airway just before the gas exchange surface.
· This method prevents muscles from receiving any additional oxygen, requiring all muscles to be supplied with enough oxygen to last the length of the dive. This shunt, on the other hand, decreases the volume of compressed gases that penetrate tissues, lowering the risk of decompression sickness
· However, the collapse of alveoli prevents any oxygen accumulation in the lungs. To prolong their dives, sea lions must reduce their oxygen consumption. The physiological control of heart rate in sea lions extends oxygen availability.
· Their on-land breeding activity is directly influenced by their abundance and haul-out behaviour. Their seasonal abundance pattern corresponds to their breeding season, which runs from January to March in the austral summer. Newborn pups, as well as male and female otariids, populate their rookeries to protect their territories.
· Male sea lions reach sexual maturity between the ages of 5 and 7, but do not become territorial until they are between the ages of 9 and 13. Late in May, the females arrive, bringing with them an increase in territorial defence through combat and boundary displays. After a week, most births consist of one pup with a perinatal period of three to thirteen days.
· Male sea lions often mate with several females in order to maximise fitness and success, leaving some males without a mate at all. Polygamous males are less likely to provide maternal care to their offspring. The resource-defense polygyny, or controlling essential female resources, is one strategy used to monopolise females.