California Sea Lion
Reading: California Sea Lion
conservation STATUS : Species or Population Dependent
climate CHANGE : Not Applicable
At the Aquarium
Our sea lions are on view in the Seals and Sea Lions Habitat .
Eastern north Pacific from Vancouver Island, British Columbia south to Baja California, Mexico including the Gulf of California .
Sea lions inhabit moderate or subtropical waters. They haul out on placid flaxen beaches, offshore rocks, and on man-made structures such as piers, boats, breakwaters, and buoys. They remain close up to the water ’ second edge of beaches during quick weather, moving inland or up coastal slopes during cool weather or at night .
The adult male ’ mho body is robust at the neck, shoulders, and chest with a rather slender back end, while females and juveniles are slim-bodied and more streamlined. These ocean lions have a long, square, and narrow snout and clear-cut, humble, external ears. long paddle-like fore flippers that end in bantam claws with hair on the upper surface extending past the wrist are used for propulsion through the water. Their hind flippers, used as rudders for steering, are much shorter and have fleshy tips and short minute hook at the end of the digits. They have a small but clear-cut tail. Mature males have a outstanding jutting brow with a large dislodge of bone called the sagittal crest. The crown is topped by a light color haircloth tuft. Unlike other sea lions, California ocean lions do not have a lion-like mane .
pornographic males are chiefly a black brown color, except for light tan areas on the face. They appear black when wet. Most males do not fade to a lighter color after molting. however, a minor number do remain light up yellow to blond their entire life. Adult females and juveniles are tan or blond except for a brusque period after molting when they are light grey to silver-grey. Molting begins at about puberty. Adult males seem to molt in January and February, with females and juveniles molting from early fall through the winter. Pups are darkness brown to black when born, fading to light brown within a few weeks. At approximately four to five months of age, pups molt to a alight grey coat, darkening to a blue cocoa that fades to light tan .
Adult male sea lions may reach a length of 2.4 thousand ( 7 foot 10 in ) and a system of weights of 390 kg ( 860 pound ). Females are markedly smaller reaching a maximum length of 2 megabyte ( 6 foot 7 in ) and a burden of 110 kg ( 240 pound ) .
These pinnipeds are opportunist feeders normally seeking prey in cool, upwelling waters near the seashore, around seamounts, along the continental shelf, and occasionally on the sea bottom, Mackerel, marketplace squid, anchovy, rockfish, and salmon are favorite food items. Food is swallowed whole without chewing. They compete with commercial and sport fishermen, stealing overcharge prey, catch from nets, and pink-orange migrating to spawning areas.
Females are mature at three years of age and males at five. These sea lions congregate in huge colonies in breed and birthing areas—the Channel Islands off the slide of central California, islands along the northern Pacific coast of Baja California including Guadalupe Island ; islands along the east coast of Baja California ; and on beaches in the mid and southerly Gulf of California. Males arrive at breeding grounds before females and set up territories that will finally include three to forty females .
give birth of sea lions takes target on estate. concisely after arrival, from late May through July, the meaning females give birth to pups conceived in the past year ’ sulfur breeding season about 12 months ago. The pup consider 6-9 kilogram ( 13-20 pound ) at parentage. Within about three weeks after giving birth, females are ready to breed again. Males compete to mate with the females and defend their district with ritualize physical displays including voice threats, aggressive pose, and occasionally physical fight. Delayed implantation of the fertilize egg in the mother ’ second uterus ensures that her pup will be born at the breed flat coat when colonies form again a year belated .
Females stay with their pups for the first seven to ten days and then begin to forage at sea for one to three days at a prison term. Returning to shore, they quickly find their pup by smell and voice. They spend a day on shore after each forage period nursing the whelp. An older puppy may accompany its mother on some scrounge trips. Younger whelp congregate in big groups to play and socialize. Pups are weaned abruptly and abandoned by their mothers normally when six months honest-to-god .
California sea lions are social animals. When hauled out they rest close to and much on acme of each other. The noise level in the colonies is intense as a leave of their forte vocalize that some have compared to a leo ’ s bellow or andiron ’ south bark. They may forms rafts or travel and play in groups of twelve or more .
These pinnipeds may spend several days to several weeks at sea forage. During this clock they dive about endlessly, taking brief surface rests. In the summer, females dive for up to four minutes to 75 megabyte ( 245 foot ). In winter, their dives are deeper and longer. The maximum dive time recorded is 12 minutes and the utmost dive depth is 536 meter ( 1,760 foot ) .
They use their flippers to help regulate their body temperature. They rest on the surface of the water on their backs with heads and flippers above the body of water. They wave their flippers in the air to absorb heat from the sunday and to lose inflame to the water .
California sea lions are well adapted to their marine environment. Limbs that evolved into flippers and body supreme headquarters allied powers europe allows effective bowel movement through the water. Their thickly fatness layer aids in temperature control. Vision is cutting and better in the urine than come out of the closet. very sensitive whisker or whiskers are an important centripetal part when the animal is hunting for food or liquid in a darkness or constricted area. Muscle tissue myoglobin stores relatively big quantities of oxygen, helping the animal during long periods under water and during deep dives. The myoglobin can supply oxygen when early oxygen sources are exhausted. Sea lions have the ability to direct oxygen-rich lineage to critical organs where it is most needed .
Female California sea lions have a life of 18-25 years. That of males is slenderly less .
Although hunted in the past, the current sea leo population has increased well along the United States west slide since the passage of the Marine Mammal Protection Act of 1972. Of the five species of ocean lions, the California ocean leo is the only one in which the population has increased. This increase in numbers has resulted in conflicts with marina owners, fishermen, and local governments as the sea lions have damaged boats and docks, ‘ stolen ’ fish from fishing gearing and salmon runs, and hauled out in numbers on popular beaches. The conflicts have escalated at the Bonneville Dam on the Columbia River in Washington State where the sea lions target salmon congregate at pisces ladders to go upriver to spawn. NOAA ’ sulfur Office of Fisheries issued permits to Washington, Oregon, and Idaho to capture or kill angstrom many as 85 sea lions at the establish of the dam for five years. The license was challenged in court and a decision was made that entirely capture in traps is permitted. Captured animals are either relocated in the wild or sent to the protected environments of menagerie or aquariums. There have been reports of trap animals being illegally shot and killed by unknown persons.
Sea lions are affected by changes in water temperature associated with climate changes such as El Niño. As the water system warms, many of their food sources move to colder waters, making it unmanageable for the ocean lions to find food finale to their reproduction areas. nurse females scrounge for food further and further away from their land-bound pups, frequently resulting in abandonment of the pups .
Nonpoint polluting runoff, ( for exercise, agricultural runoff ; pesticides, herbicides, and fertilizers used in family gardening ), increases the nutrient load of seawater much resulting in harmful alga blooms, a crimson tide that produces domoic acid poison in ocean lions and other marine mammals and seabirds .
Marine mammal concern centers per annum treat ocean lions affected by these climatic changes, epenthetic and bacterial infections, and human-caused injuries. The goal is to rehabilitate the animals so they can be returned to the wilderness. If a decisiveness is made that the animal could not survive in the wilderness, such as is often the case with abandoned pups, they are released to protected environments. Odin, one of the Aquarium of the Pacific ’ s former ocean lions, came from the Marine Mammal Care Center at Fort McArthur in San Pedro, California .