California Sea Lion
West coast of North America, from British Columbia south to Baja California and the Sea of Cortez.
Inhabit rocky and sandy beaches of coastal islands and mainland shorelines along the coasts.
California sea lines are characterized by a streamlined body and powerful flippers. California sea lions range in color from chocolate brown in males to a lighter, golden brown in females. They have a "dog-like" face, and at around five years of age, males develop a bony bump on top of their skull called a sagittal crest. This is a sexually dimorphic trait and helps the males and female easily recognize one another. The top of a male's head often gets lighter in color with age. California sea lions do not have lion-like manes like other sea lion species.
They belong to a group of seals called otariids, or eared seals. This group has external ear flaps and large flippers that they use to "walk" on land. Their hind flippers are shorter than the front flippers and can be rotated forward to help it shuffle along on land. Sea lions have external ear flaps, large eyes and 40 to 60 whiskers. California sea lions also have thick layers of blubber to insulate their bodies from the chilly ocean waters.
Sea lions swim with up-and-down, wing-like strokes of their fore-flippers and are very agile and maneuverable when swimming. They are capable of reaching speeds in excess of 13 miles per hour but generally swim at much slower speeds.
When diving, California sea lions slow their heart rates to allow them to remain underwater for nearly ten minutes before surfacing to breathe. They also have a much higher blood volume than non-diving animals of the same size. This creates a greater oxygen binding capacity. During a dive, the blood is shunted or moved away from their extremities and concentrated in the heart and central nervous system. The muscle of California sea lions has a high concentration of the oxygen-binding protein myoglobin to help prevent muscle oxygen deficiency. These adaptations allow them to dive to depths of 899 feet.
The trained "seals" in zoos and aquariums are usually California sea lions. Sea lions are very social animals and live in colonies that may number in the thousands, especially during the breeding season. They often gather on rocky beaches, and on man-made structures such as docks. They frequently lie near and on top of each other. They will share haul-out space with northern elephant seals, harbor seals, northern fur seals, and Steller sea lions. California sea lions frequently interact with these species in much the same way as they interact among themselves.
In the water, they are often seen floating on the surface in small groups called rafts. To regulate their body temperatures, sea lions raise their flippers out of the water. The blood vessels absorb or release heat to the environment, a little bit like a solar panel.
Younger sea lions, more playful than adults, ride the surf and chase each other. They are sometimes seen "porpoising," or jumping out of the water, presumably to speed up their swimming. Sea lions have also been seen "surfing" breaking waves. They are faster than any other sea lion or seal. They can reach top swimming speeds of 25 miles an hour.
At the beginning of the breeding season, males establish a territory by barking, biting, and shoving. Although they patrol their territory's boundaries, they do not prevent the females in their harem from leaving. A male sea lion may eat more than 15 pounds of fish a day and depends on healthy fish stocks.
Males arrive on the breeding grounds before females and set up territories, which they defend aggressively. Females arrive and segregate into harems of 3-40 individuals, depending on the size and strength of the male. Soon after they arrive, females give birth to pups from the previous year's breeding season, and within a few days, enter estrous. Mating takes place on land. A period of delayed implantation insures that the young will be born in a year, when the breeding herds again form. Breeding takes place a few weeks after birth. Males patrol territories and bark almost continuously during the breeding season. The gestation is about 11 months.
Females give birth, usually to a single pup. They stay with their newborn for several days, before returning to the sea to feed, returning every few days to nurse their young. Females often give birth in large pupping ground. A single rookery may include as 200 sea lion pups.
To find her pup, the mother vocalizes, listening for a bleat in response. When she thinks she has located it, she inspects the pup by sight and smell before letting it nurse. Over time, mothers and their young swim together more and more; the young are weaned at about 11 to 12 months of age.
• California sea lions are among the most vocal mammals. Their vocalizations include barks, roars, growls, and grunts.
• They have excellent eyesight and hearing both in the water and on land.
• Pups molt twice in the first six months of their life. Adults molt annually, shedding and replacing their guard hairs and underfur.
About Our Animals:
The Zoo currently is home to two male sea lions.
|Did YOU Know?|
|California sea lions may hunt continuously for up to 30 hours, with each dive lasting three to five minutes.|
|Length:||Females measure 6-7 feet in length. Males measure 7-8 feet in length.|
|Weight:||Males weigh up to 1,200 pounds. Females weigh 110-240 pounds.|
|Average Lifespan:||Less than 30 years.|
|Wild Diet:||Octopus, fish and squid.|
|Zoo Diet:||Fish and squid|
|Predators:||White sharks and killer whales.|
|This is an ssp animal|
|Where at the Zoo?||Rocky Shores|