Sea lion facts for kids
Quick facts for kids Sea lion |
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| California sea lion (Zalophus californianus) | |
Scientific classification  |
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| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Clade: | Pinnipedia |
| Family: | Otariidae |
| Subfamily: | Otariinae Gray 1825 |
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Eumetopias |
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Sea lions are several pinnipeds from the family Otariidae (eared seals). They live all around the world, except in the Atlantic Ocean. Together with the fur seals, they make up the family Otariidae, eared seals.
Male sea lions have thick fur around the face and neck, which sometimes looks like a lion's mane. That's how they got the name "sea lion". Some, like the Steller sea lion, can actually roar! Of course, these pinnipeds are not really lions at all, but they are mammals. Like lions, they have fur, breathe air, give birth to live young, and feed milk to their young. They also eat meat, though sea lions eat the meat of fishes, squids, and sea birds instead of land animals. Sea lions are also fierce fighters, just like lions.
Contents
Physiology
Diving adaptations
The sea lions' bodies control heart rate, gas exchange, digestion rate, and blood flow to allow them to dive for a long period of time and prevent side effects of high pressure at depth.
One of the ways sea lions deal with the extreme pressures is by limiting the amount of gas exchange that occurs when diving. They can reduce their heart rate to well below surface rates. Also, sea lions can limit digestion rate and decrease it by at least 54%.
Parasites and diseases
Galapagos sea lions (Zalophus wollebaeki) can be infected with Philophthalmus zalophi, an eye fluke. These infections have heavy impacts on the survival of juveniles. The disease appears to be compounded by global warming. Sea lions are affected by the parasites from the early ages of 3 weeks old up until the age of 4 to 8 months. The parasites found in the eye fluke did serious damage to the eye. From the data collected, 21 of the 91 survived; with a total of 70 deaths in just a span of two years. The parasites are attacking the pups at such young ages; thus causing the pups to not reach the age of reproduction. Other parasites, like Anisakis and heartworm can also infect sea lions.
Similarly, climate change has resulted in increased toxic algae blooms in the oceans. These toxins are ingested by sardines and other fish which are then eaten by the sea lions, causing neurological damage and diseases such as epilepsy.
Population
Otaria flavescens (South American sea lion) lives along the Chilean coast with a population estimate of 165,000. According to the most recent surveys in northern and southern Chile the sealing period of the middle twentieth century that left a significant decline in sea lion population is recovering. The recovery is associated with less hunting, otariids rapid population growth, legislation on nature reserves, and new food resources. Haul-out patterns change the abundance of sea lions at particular times of the day, month, and year. Patterns in migration relate to temperature, solar radiation, and prey and water resources. Studies of South American sea lions and other otariids document maximum population on land during early afternoon, potentially due to haul-out during high air temperatures. Adult and subadult males do not show clear annual patterns, maximum abundance being found from October to January. Females and their pups hauled-out during austral winter months of June to September.
Interactions with humans
South American sea lions have been greatly impacted by human exploitation. The number of sea lions declined due hunting of the species and exploitation of the species’ environment. Although sealing has been put to a halt in many countries, such as Uruguay, the sea lion population continues to decline because of the drastic effects humans have on their ecosystems. As a result, South American sea lions have been foraging at higher tropical latitudes than they did prior to human exploitation.
Fishermen play a key role in the endangerment of sea lions. Sea lions rely on fish, like pollock, as a food source and have to compete with fishermen for it. When fishermen are successful at their job, they greatly reduce the sea lion's food source, which in turn endangers the species.
Sea lion attacks on humans are rare, but when humans come within approximately 2.5 meters (8 ft), it can be very unsafe. In April 2015, a sea lion attacked a 62-year-old man who was boating with his wife in San Diego. The attack left the man with a punctured bone. In May 2017, a sea lion grabbed and pulled a girl into the water by her dress before retreating. The child was sitting on a pier side in British Columbia while tourists were illegally feeding the sea lions when the incident took place. She was pulled out of the water with minor injuries.
Sea lions have also been a focus of tourism in Australia and New Zealand. One of the main sites to view sea lions is in the Carnac Island Nature Reserve near Perth in Western Australia. This tourist site receives over 100,000 visitors, many of whom are recreational boaters and tourists, who can watch the male sea lions haul out on to the shore. They have sometimes been called "the unofficial welcoming committee of the Galápagos Islands".
Interesting facts about sea lions
- Sea lions are related to walruses and seals.
- The sea lions have six extant and one extinct species (the Japanese sea lion) in five genera.
- They have an average lifespan of 20–30 years.
- A male California sea lion weighs on average about 300 kg (660 lb) and is about 2.4 m (8 ft) long, while the female sea lion weighs 100 kg (220 lb) and is 1.8 m (6 ft) long.
- The largest sea lions are Steller's sea lions, which can weigh 1,000 kg (2,200 lb) and grow to a length of 3.0 m (10 ft).
- Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight (about 6.8–15.9 kg (15–35 lb)) at a single feeding.
- Sea lions can move around 16 knots (30 km/h; 18 mph) in water and at their fastest they can reach a speed of about 30 knots (56 km/h; 35 mph).
- Three species, the Australian sea lion, the Galápagos sea lion and the New Zealand sea lion, are listed as endangered.
Gallery
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| A gathering of more than 40 sea lions off the coast of California | A military sea lion on board a U.S. Navy ship | A sea lion at the Memphis Zoo | A sea lion pup sleeping at Pantai Inn |
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| A sea lion in Malibu, California | Sea Lion at Monterey Breakwater | A sea lion sleeps in the Ballestas Islands, Peru | A group of sea lions rest in the Ballestas Islands, Peru |
See also
In Spanish: Otariinae para niños
