California sea lion

The California sea lion (Zalophus californianus) is a coastal eared seal native to western North America. It is one of six species of sea lion. Its natural habitat ranges from southeast Alaska to central Mexico, including the Gulf of California. Sea lions are sexually dimorphic; males are larger than females, and have a thicker neck, and protruding sagittal crest. They mainly haul-out on sandy or rocky beaches, but they also frequent manmade environments such as marinas and wharves. Sea lions feed on a number of species of fish and squid, and are preyed on by orcas and white sharks.

California sea lions have a polygynous breeding pattern. From May to August, males establish territories and try to attract females with which to mate. Females are free to move in between territories, and are not coerced by males. Mothers nurse their pups in between foraging trips. Sea lions communicate with numerous vocalizations, notably with barks and mother-pup contact calls. Outside their breeding season, sea lions spend much of their time at sea, but they come to shore to molt.

Sea lions are particularly intelligent, can be trained to perform various tasks and display limited fear of humans if accustomed to them. Because of this, California sea lions are a popular choice for public display in zoos, circuses and oceanariums, and are trained by the United States Navy for certain military operations. The International Union for Conservation of Nature (IUCN) lists the species as Least Concern due to its abundance. To protect fish, the US states of Oregon and Washington engage in annual kill quotas of sea lions.

California sea lion
Sea Lions At La Jolla Cove - 32
Male in La Jolla, California
California sea lion in La Jolla (70568)
Female in La Jolla, California
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Otariidae
Genus: Zalophus
Species:
Z. californianus
Binomial name
Zalophus californianus
(Lesson, 1828)
Zalophus californianus distribution
California sea lion breeding range in dark blue, total range light blue. In red is the range of the Galapagos Sea Lion.

Taxonomy

Zalophus californianus J. Smit
Lithography by Joseph Smit.

The California sea lion was described by René Primevère Lesson, a French naturalist, in 1828. It is grouped with other sea lions and fur seals in the family Otariidae. Otariids, also known as eared seals, differ from true seals in having external ear flaps, and proportionately larger foreflippers and pectoral muscles. Along with the Galapagos sea lion and the extinct Japanese sea lion, the California sea lion belongs to the genus Zalophus, which derives from the Greek words za, meaning "intensive," and lophus, meaning "crest."[2] This refers to the protruding sagittal crest of the males, which distinguishes members of the genus.[3]

Traditionally, the Galapagos sea lion and Japanese sea lion were classified as subspecies of the California sea lion. However, a genetic study in 2007 found that all three are in fact separate species.[4] The lineages of the California and Japanese sea lion appear to have split off 2.2 million years ago during the Pliocene.[5] The California sea lion differs from the Galapagos sea lion in its greater sexual dimorphism.[3] The Steller sea lion is the closest extant relative of the Zalophus sea lions, being a sister taxon.[6]

Appearance, physiology, and movement

Zalophus californianus 01
California sea lion skeleton

Being sexually dimorphic, California sea lions differ in size, shape, and coloration between the sexes. Males are typically around 2.4 m (7.9 ft) long and weigh up to 350 kg (770 lb), while females are typically around 1.8 m (5.9 ft) and weigh up to 100 kg (220 lb).[3] Females and juveniles have a tawny brown pelage,[3] although they may be temporarily light gray or silver after molting.[7] The pelage of adult males can be anywhere from light brown to black, but is typically dark brown.[3] The face of adult males may also be light tan in some areas. Pups have a black or dark brown pelage at birth.[7] Although the species has a slender build, adult males have robust necks, chests, and shoulders.[7] Adult males also have a protruding crest which gives them a "high, domed forehead";[8] it is tufted with white hairs.[3] They also have manes, which are less developed than those of adult male South American and Steller sea lions.[8] Both sexes have long, narrow muzzles.[7]

As an otariid, the California sea lion relies on its foreflippers to propel itself when swimming. This form of aquatic locomotion, along with its streamlined body, effectively reduces drag underwater. Its foreflipper movement is not continuous; the animal glides in between each stroke.[9] The flexibility of its spine allows the sea lion to bend its neck backwards far enough to reach its hindflippers. This allows the animal to make dorsal turns and maintain a streamlined posture.[10] When moving on land, the sea lion is able to turn its hindflippers forward and walk on all fours. It moves the foreflippers in a transverse, rather than a sagittal, fashion. In addition, it relies on movements of its head and neck more than its hindflippers for terrestrial locomotion.[11] Sea lions may travel at speeds of around 10.8 km/h (6.7 mph),[12] and can dive at depths of 274 m (899 ft) and for up to 9.9 minutes, though most dives are typically 80 m (260 ft) and last less than 3 minutes.[13]

Lion de mer Amnéville 01
Sea lion swimming underwater

Sea lions have color vision, though it is limited to the blue-green area of the color spectrum. This is likely an adaptation for living in marine coastal habitats.[14] Sea lions have fairly acute underwater hearing, with a hearing range of 0.4–32 kHz.[15] Sea lions rely on their whiskers or vibrissae for touch and detection of vibrations underwater. Compared to the harbor seal, the California sea lion's vibrissae are smoother and less specialized and thus perform less when following hydrodynamic trails, although they still perform well.[16]

Ecology

Range and habitat

Santa-Barbara-Island-Sea-Lion-Rookery
Sea lion rookery on Santa Barbara island

The California sea lion ranges along the western coast and islands of North America, from southeast Alaska to central Mexico. Mitochondrial DNA sequences in 2009 have identified five distinct California sea lion populations: the U.S. or Pacific Temperate stock, the Western Baja California or Pacific Tropical stock, and the Southern, Central, and Northern Gulf of California stocks.[6] The U.S. stock breeds mainly in the Channel Islands, although some breeding sites may be established in northern California, and females are now commonly found there.[1] The Western Baja California stock mainly breeds near Punta Eugenia and at Isla Santa Margarita. The above-mentioned stocks are separated by the Ensenada Front. The stocks of the Gulf of California live in the shallow waters of the north (Northern stock), the tidal islands near the center (Central stock), and the mouth of the bay (Southern stock). The stock status of the sea lions at the deep waters of the central bay has not been analyzed.[6]

Vagrants can reach western north pacific such as on Commander Islands.[17] Although several otariinae have been recorded around Japanese archipelago in recent years, their exact origins are unclear.[18]

Zalophus californianus2
Sea lions in Santa Cruz, California

During the breeding season, sea lions gather on both sandy and rocky shores. On warm days, they lie closer to the water. At night or in cool weather, they travel farther inland or to higher elevations.[7] Non-breeding individuals may gather at marinas, wharves, or even navigational buoys. California sea lions can also live in fresh water for periods of time, such as near Bonneville Dam, nearly 150 miles up the Columbia River.[19] In 2004 a healthy sea lion was found sitting on a road in Merced County, California, almost a hundred miles upstream from the San Francisco Bay and half a mile from the San Joaquin River.[20]

Diet and predation

California sea lions feed on a wide variety of seafood, mainly squid and fish, and sometimes clams. Commonly eaten fish and squid species include salmon, hake, Pacific whiting, anchovy, herring, rockfish, lamprey, dogfish, and market squid.[21] They mostly forage near mainland coastlines, the continental shelf, and seamounts. They may also search along the ocean bottom.[7] California sea lions may eat alone or in small to large groups, depending on the amount of food available. They sometimes cooperate with other predators, such as dolphins, porpoises, and seabirds, when hunting large schools of fish.[22] Sea lions sometimes follow dolphins and exploit their hunting efforts.[3] Adult females feed between 10–100 km (6.2–62.1 mi) from shore.[12] Males may forage as far as 450 km (280 mi) from shore when water temperatures rise.[23] They also have learned to feed on steelhead and salmon below fish ladders at Bonneville Dam and at other locations where fish must queue in order to pass through dams and locks that block their passage.

Sea lions are preyed on by killer whales and large sharks. At Monterey Bay, California sea lions appear to be the more common food items for transient mammal-eating killer whale pods.[24] The sea lions may respond to the dorsal fin of a killer whale and remain vigilant, even when encountering resident fish-eating pods.[25] Sea lions are also common prey for white sharks. They have been found with scars made by attacks from both white sharks and shortfin mako sharks. Sharks attack sea lions by ambushing them while they are resting at the surface.[26] Sea lions that are attacked in the hindquarters are more likely to survive and make it to the shore.[27]

Life history

Reproductive behavior and parenting

Sea lion beach
Sea lion rookery

California sea lions breed gregariously between May and August, when they arrive at their breeding rookeries. When establishing a territory, the males will try to increase their chances of reproducing by staying on the rookery for as long as possible. During this time, they will fast, relying on a thick layer of fat called blubber for energy. Size and patience allow a male to defend his territory more effectively; the bigger the male, the more blubber he can store and the longer he can wait. A male sea lion usually keeps his territory for around 27 days. Females have long parturition intervals, and thus the males do not establish their territories until after the females give birth. Most fights occur during this time. After this, the males rely on ritualized displays (vocalizations, head-shaking, stares, bluff lunges, and so on) to maintain their territorial boundaries. Since temperatures can reach over 30 °C (86 °F) during this time, males must include water within their territories. Some territories are underwater, particularly those near steep cliffs.[28] Sea lions that fail to establish a territory are driven out to sea or gather at a nearby beach.[3]

Sea lion mother and pup
Sea lion mother with pup

Before mating begins, females gather into "milling" groups of 2–20 individuals. The females in these groups will mount each other as well as the males. These groups begin to disintegrate as the females begin to mate.[3] The territorial and mating system of the California sea lion has been described as similar to a lek system, as females appear to choose their mates while moving though different territories.[29] They avoid males that are too aggressive or energetic. Males are usually unable to prevent females from leaving their territories,[3] particularly in water.[30] Mating may occur outside the rookeries, between non-territorial males and females, as the latter move to and from the mating site. In some rookeries, copulation may be monopolized by a few males, while at others, a single male may sire no more than four pups.[30]

Female California sea lions have a 12-month reproductive cycle, consisting of a 9-month actual gestation and a 3-month delayed implantation of the fertilized egg before giving birth in June or July. Interbirth intervals are particularly long for this species, being 21 days for sea lions off California and more than 30 days for sea lions in the Gulf of California.[30] Females remain with their pups on shore for 10 days and nurse them. After this, females will go on foraging trips lasting as long as three days, returning to nurse their pups for up to a day. Pups left on shore tend to gather in nurseries to socialize and play.[7] When returning from a trip, females call their pups with distinctive calls to which the pups will reply in kind. A mother and pup can distinguish each other's calls from those of other mothers and pups. At first, reunions largely depend on the efforts of the mothers. However, as pups get older, they get more involved in reunions.[31] Older pups may sometimes join their mothers during their foraging trips.[7] Adult male California sea lions play no role in raising pups, but they do take more interest in them than adult males of other otariid species; they have even been observed to help shield swimming pups from predators.[32] Pups are weaned by a year but can continue to suckle for another year.[3]

Communication

Barking sea lions pursuing a boat

California sea lions communicate with a range of vocalizations. The most commonly used one is their characteristic bark. Territorial males are the loudest and most continuous callers, and barks are produced constantly during the peak of the breeding season. Sea lions bark especially rapidly when excited. The barks of territorial and non-territorial males sound similar, although those of the former are deeper. Males may bark when threatening other males or during courtship. The only other vocalization made by territorial males is a "prolonged hoarse grunt sound" made when an individual is startled by a human. This vocalization is also made by groups of non-reproductive males.[33]

Female sea lions are less vocal. Their barks, high-pitched and shorter than those made by males, are used in aggressive situations. Other aggressive vocalizations given by females include the "squeal", the "belch", and the "growl". The sound a female sea lion gives when calling her pups is called a "pup-attraction call", described as "loud" and "brawling". Pups respond with a "mother-response call", which is similar in structure. Pups will also bleat or bark when playing or in distress.[33] California sea lions can produce vocalizations underwater. These include "whinny" sounds, barks, buzzings, and clicks.[34]

Nonbreeding activities

Outside the breeding season, males migrate to the northern ends of the species range to feed, while females forage near the breeding rookeries.[3] Sea lions can stay at sea for as long as two weeks at a time. They make continuous dives, returning to the surface to rest. Sea lions may travel alone or in groups while at sea and haul-out between each sea trip. Adult females and juveniles molt in autumn and winter; adult males molt in January and February. Gulf of California sea lions do not migrate; they stay in the Gulf year-round.[30]

Intelligence and trainability

US Navy 030213-N-3783H-011 Zak, a 375-pound California sea lion, leaps back into the boat after a harbor-patrol training mission
Zak, a 375 lb (170 kg) Navy sea lion leaps back into the boat after a harbor-patrol training mission.

Marine biologist Ronald J. Schusterman and his research associates have studied sea lions' cognitive ability. They have discovered that sea lions are able to recognize relationships between stimuli based on similar functions or connections made with their peers, rather than only the stimuli's common features.[35] Sea lions have demonstrated the ability to understand simple syntax and commands when taught an artificial sign language. However, the sea lions rarely used the signs semantically or logically.[36] In 2011, a California sea lion named "Ronan" was recorded bobbing her head in synchronization to musical rhythms.[37] This "rhythmic entrainment" was previously seen only in humans, parrots and other birds possessing vocal mimicry.[38]

Captive sea lion performing
Sea lion, Central Park Zoo
A California sea lion at Central Park Zoo. It has climbed to the edge of its tank awaiting feeding, showing awareness of its regular feeding time.

Because of their intelligence and trainability, California sea lions have been used by circuses and marine mammal parks to perform various tricks such as throwing and catching balls on their noses, running up ladders, or honking horns in a musical fashion. Trainers reward their animals with fish, which motivates them to perform. For ball balancing, trainers toss a ball at a sea lion so it may accidentally balance it or hold the ball on its nose, thereby gaining an understanding of what to do. A sea lion may go through a year of training before performing a behavior for the public. However, its memory allows it to perform a behavior even after three months of resting.[32] Some organizations, such as the Humane Society of the United States and World Animal Protection, object to using sea lions and other marine mammals for entertainment, claiming the tricks are "exaggerated variations of their natural behaviors" and distract the audience from the animal's unnatural environment.[39] Less entertainment-oriented zoos may still encourage animal play by throwing fish at animals in different directions and providing play equipment.[40]

The California sea lion is used in military applications by the U.S. Navy Marine Mammal Program, including detecting naval mines and enemy divers. In the Persian Gulf, the animals can swim behind divers approaching a US naval ship and attach a clamp with a rope to the diver's leg. Navy officials say the sea lions can do this in seconds, before the enemy realizes what happened.[41] Organizations like PETA believe that such operations put the animals in danger.[42] However, the Navy insists that the sea lions are removed once their mission is complete.[43]

Status

Sealions on Pier 39, SF, CA, jjron 26.03.2012
Hundreds of California sea lions bask on Pier 39 in San Francisco, where they are welcomed as a tourist attraction.

The IUCN lists the California sea lion as Least Concern due to "its large and increasing population size."[1] The estimated population is 238,000–241,000 for the U.S. or Pacific Temperate stock, 75,000–85,000 for the Western Baja California or Pacific Tropical stock, and 31,393 for the population in the Gulf of California.[6] Off the Pacific coast of the United States, sea lions are so numerous that they are close to carrying capacity, while the Gulf of California population declined by 20% by 2008. Sea lions may be killed when in conflict with fishermen, by poaching, and by entanglements in man-made garbage. They are also threatened by pollutants like DDT and PCB which accumulate in the marine food chain.[1]

100-Shooting Sea Lions
Shooting sea lions, ca. 1870s

In the United States, the California sea lion is protected on the federal Marine Mammal Protection Act (MMPA), passed in 1972, which outlaws hunting, killing, capture, and harassment of the animal. In 1994 an amendment to the Act allowed for the possibility of limited lethal removal of pinnipeds preying on endangered salmonids should the level of predation be documented to have a significant adverse impact on the decline or recovery of ESA-listed salmonids.[44] Applications have been granted for removal of several individual sea lions at Ballard Locks[45] and at the Bonneville Dam, where up to 92 sea lions can be killed each year for a 5-year period.[46] Critics have objected to the killing of the sea lions, pointing out that the level of mortality permitted as a result of recreational and commercial fisheries in the river and as part of the operation of hydroelectric dams pose a greater threat to the salmon.[47]

These animals exploit more man-made environments like docks for haul-out sites. Many docks are not designed to withstand the weight of several resting sea lions which cause major tilting and other problems. Wildlife managers have used various methods to control the animals and some city officials have redesigned docks so they can better withstand them.[48][49]

2015 Californian shore sea lions pups crisis

In January and February 2015, 1450 malnourished or sick sea lion pups were found along stretches of the California coast, and estimations give a higher number of dead pups. The National Oceanic and Atmospheric Administration has pointed to unprecedentedly warm Pacific coastal waters, related to Pacific decadal oscillation and El Niño, as the likely cause. Elevated water temperatures reduced the abundance of anchovies, sardines and mackerel, principal components of the sea lion pup diet during nursery season.[50] This caused many sea lion pups to starve, while others died when they took to open waters in search of food at too early an age [51]. Several months earlier, in the Summer of 2014, a large number of Cassin's auklet chicks died during the fledging period due to similar circumstances brought about by elevated water temperatures.[52]

Oregon and Washington state governments annual killings

In November 2018, the State of Oregon obtained a permit to kill 93 sea lions per year below Willamette Falls. Under a similar program, Oregon and Washington had killed over 150 sea lions on the Columbia river by January 2019.[53][54]

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  47. ^ "Bonneville Dam Sea Lions Under Siege". The Humane Society of the United States. Retrieved 17 October 2013.
  48. ^ French, C. (April 10, 2013). "Sea Lions Take Over Ventura Docks". the Log.com. Retrieved August 17, 2013.
  49. ^ Bruscas, A. (July 27, 2012). "Shocking new idea for sea lion control". The Daily World.com. Archived from the original on September 21, 2013. Retrieved August 17, 2013.
  50. ^ Hecht, Peter (2015-03-07). "Sick, starving sea lion pups wash up in record numbers on California coast". The Sacramento Bee. Retrieved 12 March 2015.
  51. ^ "More Than 100 Sick Sea Lion Flooded On California Coastline". Retrieved 12 March 2015.
  52. ^ "Mass Death of Seabirds in Western U.S. Is 'Unprecedented'". news.nationalgeographic.com/. 2015-01-24. Retrieved 12 March 2015.
  53. ^ GILLIAN FLACCUS (10 January 2019). "Oregon begins killing sea lions after relocation fails". Associated Press. Retrieved 10 January 2019. In a similar program, Oregon and Washington have already killed more than 150 sea lions below the Bonneville Dam on the Columbia River to protect threatened and endangered salmon.
  54. ^ "California Sea Lion Management: Restoring balance between predators and salmon". Oregon Department of Fish and Wildlife. Retrieved 17 October 2013.

External links

Animal language

Animal languages are forms of non-human animal communication that show similarities to human language. Animals communicate by using a variety of signs such as sounds or movements. Such signing may be considered complex enough to be called a form of language if the inventory of signs is large, the signs are relatively arbitrary, and the animals seem to produce them with a degree of volition (as opposed to relatively automatic conditioned behaviors or unconditioned instincts, usually including facial expressions). In experimental tests, animal communication may also be evidenced through the use of lexigrams (as used by chimpanzees and bonobos). While the term "animal language" is widely used, researchers agree that animal languages are not as complex or expressive as human language.

Many researchers argue that animal communication lacks a key aspect of human language, that is, the creation of new patterns of signs under varied circumstances. (In contrast, for example, humans routinely produce entirely new combinations of words.) Some researchers, including the linguist Charles Hockett, argue that human language and animal communication differ so much that the underlying principles are unrelated. Accordingly, linguist Thomas A. Sebeok has proposed to not use the term "language" for animal sign systems. Marc Hauser, Noam Chomsky, and W. Tecumseh Fitch assert an evolutionary continuum exists between the communication methods of animal and human language.

Bluespotted poacher

The Bluespotted poacher (Xeneretmus triacanthus) is a fish in the family Agonidae (poachers). It was described by Charles Henry Gilbert in 1890, originally in the genus Xenochirus. It is a marine, deep water-dwelling fish which is known from British Columbia, Canada to northern central Baja California, Mexico, in the eastern Pacific Ocean. It dwells at a depth range of 73–373 metres, and inhabits soft benthic sediments. Males can reach a maximum total length of 18 centimetres.The Bluespotted poacher is preyed on by the California sea lion.

Eared seal

An eared seal or otariid or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera (another species became extinct in the 1950s) and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus (odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans and the southern Indian and Atlantic Oceans. They are conspicuously absent in the north Atlantic.

The words 'otariid' and 'otary' come from the Greek otarion meaning "little ear", referring to the small but visible external ear flaps (pinnae), which distinguishes them from the phocids.

Fauna of California

The fauna of the State of California may be the most diverse in the United States of America. Of the Lower 48 conterminous states, California has the greatest diversity in climate, terrain and geology in general. The state's six life zones are the lower Sonoran (desert); upper Sonoran (foothill regions and some coastal lands); transition (coastal areas and moist northeastern counties); and the Canadian, Hudsonian, and Arctic zones, comprising California's highest elevations. California’s diverse geography gives rise to dozens of different ecosystems, each of which has its own unique native plants and animals. California is a huge state, the 3rd largest in the U.S., and can range broadly in habitat type.Earth scientists typically divide California into eleven distinct geomorphic provinces with clearly defined boundaries. They are, from north to south, the Klamath Mountains, the Cascade Range, the Modoc Plateau, the Basin and Range, the Coast Ranges, the Central Valley, the Sierra Nevada, the Transverse Ranges, the Mojave Desert, the Peninsular Ranges, and the Colorado Desert. Here, the Los Angeles Basin, the Channel Islands, and the Pacific Ocean are treated as distinct regions.

Common animals that live throughout all the state include raccoons, weasels, otters, beavers, hawks, lizards, owls, coyotes, skunks, snakes, cougars, black bears, deers, squirrels and whales. As of 2013, there are 634 bird species on the California Birds Records Committee, ten of which are introduced species which are not native to the state. The California quail, the official state bird, has a breeding habit of mainly shrubby areas and open woodland. Another bird which winters in California is the American white pelican which is a large seabird, with a wingspan reaching up to 110 inches (280 cm).

Venomous spiders in California include Arizona recluse, baja recluse, chilean recluse, desert recluse, martha's recluse, russell's recluse, brown widow and western black widow.

Giza Zoo

The Giza Zoo is a zoological garden in Giza, Egypt. It is one of the few green areas in the city, and includes Giza's largest park. The zoo covers about 80 acres (32 ha), and is home to many endangered species, as well as a selection of endemic fauna.

Rare species have been successfully bred in the zoo - including the first California sea lion to be born in the Middle East in 2002.

Hydrodynamic reception

Hydrodynamic reception refers to the ability of some animals to sense water movements generated by biotic (conspecifics, predators, or prey) or abiotic sources. This form of mechanoreception is useful for orientation, hunting, predator avoidance, and schooling. Frequent encounters with conditions of low visibility can prevent vision from being a reliable information source for navigation and sensing objects or organisms in the environment. Sensing water movements is one resolution to this problem.This sense is common in aquatic animals, the most cited example being the lateral line system, the array of hydrodynamic receptors found in fish and aquatic amphibians. Arthropods (including crayfish and lobsters) and some mammals (including pinnipeds and manatees) can use sensory hairs to detect water movements. Systems that detect hydrodynamic stimuli are also used for sensing other stimuli. For example, sensory hairs are also used for the tactile sense, detecting objects and organisms up close rather than via water disturbances from afar. Relative to other sensory systems, our knowledge of hydrodynamic sensing is rather limited. This could be because humans do not have hydrodynamic receptors, which makes it difficult for us to understand the importance of such a system. Generating and measuring a complex hydrodynamic stimulus can also be difficult.

Japanese sea lion

The Japanese sea lion (Japanese: ニホンアシカ, Hepburn: Nihon ashika, Zalophus japonicus) was an aquatic mammal thought to have become extinct in the 1970s. It was considered to be a subspecies of California sea lion (Z. californianus) until 2003. They inhabited the Sea of Japan, especially around the coastal areas of the Japanese Archipelago and the Korean Peninsula. They generally bred on sandy beaches which were open and flat, but sometimes in rocky areas. They were hunted commercially in the 1900s, leading to their extinction, but there are efforts to reintroduce sea lions to the Sea of Japan.

List of mammals of Alabama

The U.S. state of Alabama is home to these known indigenous mammal species. Historically, the state's indigenous species included one armadillo species, sixteen bat species, thirteen carnivore species, six insectivore species, one opossum species, four rabbit species, twenty-two rodent species, and three ungulate species. Four of these native species have become extirpated within the state, including the American bison, cougar, elk, and the red wolf.There are six known introduced mammal species in the state. These include the black rat, brown rat, fallow deer, feral swine, house mouse, and nutria. Several other mammal species have had verifiable sightings within the state, but are believed by biologists to be without established breeding populations. These include the California sea lion (in Mobile Bay), ring-tailed cat, and jaguarundi.Human predation and habitat destruction has placed several mammal species at risk of extirpation or extinction. The Alabama Department of Conservation and Natural Resources lists the conservation status of each species within the state with a rank of lowest, low, moderate, high, and highest concern.

Lutrogale

Lutrogale is a genus of otters, with only one extant species—the smooth-coated otter.

Ojo de Liebre Lagoon

Ojo de Liebre Lagoon (formerly known as Scammon's Lagoon), translated into English as "hare eye lagoon", is a coastal lagoon located in Mulegé Municipality near the town of Guerrero Negro in the northwestern Baja California Sur state of Mexico. It lies approximately halfway between the southern tip of the Baja California Peninsula and the U.S.-Mexico border, opening onto the Pacific Ocean.

The lagoon is within the Vizcaíno Biosphere Reserve UNESCO World Heritage Site, and is a Ramsar wetlands site. It also is the site of the biggest commercial saltworks plant in the world. It is an important habitat for the reproduction and wintering of the gray whale and harbor seal, as well as other marine mammals including the California sea lion, northern elephant seal and blue whale. Four species of endangered marine turtles reproduce there. It is an important refuge for waterfowl in the winter.Encompassing both a UNESCO World Heritage Site and a major salt plant, Laguna Ojo de Liebre embodies the diverse worlds of natural habitat and industrialization.Tourism, now closely controlled, was formerly a threat to the gray whales.

Pinniped

Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora and their closest living relatives are believed to be bears and the superfamily of musteloids (weasels, raccoons, skunks, and red pandas), having diverged about 50 million years ago.

Seals range in size from the 1 m (3 ft 3 in) and 45 kg (99 lb) Baikal seal to the 5 m (16 ft) and 3,200 kg (7,100 lb) southern elephant seal, which is also the largest member of the order Carnivora. Several species exhibit sexual dimorphism. They have streamlined bodies and four limbs that are modified into flippers. Though not as fast in the water as dolphins, seals are more flexible and agile. Otariids use their front limbs primarily to propel themselves through the water, while phocids and walruses use their hind limbs. Otariids and walruses have hind limbs that can be pulled under the body and used as legs on land. By comparison, terrestrial locomotion by phocids is more cumbersome. Otariids have visible external ears, while phocids and walruses lack these. Pinnipeds have well-developed senses—their eyesight and hearing are adapted for both air and water, and they have an advanced tactile system in their whiskers or vibrissae. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water, and, other than the walrus, all species are covered in fur.

Although pinnipeds are widespread, most species prefer the colder waters of the Northern and Southern Hemispheres. They spend most of their lives in the water, but come ashore to mate, give birth, molt or escape from predators, such as sharks and killer whales. They feed largely on fish and marine invertebrates; but a few, like the leopard seal, feed on large vertebrates, such as penguins and other seals. Walruses are specialized for feeding on bottom-dwelling mollusks. Male pinnipeds typically mate with more than one female (polygyny), although the degree of polygyny varies with the species. The males of land-breeding species tend to mate with a greater number of females than those of ice breeding species. Male pinniped strategies for reproductive success vary between defending females, defending territories that attract females and performing ritual displays or lek mating. Pups are typically born in the spring and summer months and females bear almost all the responsibility for raising them. Mothers of some species fast and nurse their young for a relatively short period of time while others take foraging trips at sea between nursing bouts. Walruses are known to nurse their young while at sea. Seals produce a number of vocalizations, notably the barks of California sea lions, the gong-like calls of walruses and the complex songs of Weddell seals.

The meat, blubber and fur coats of pinnipeds have traditionally been used by indigenous peoples of the Arctic. Seals have been depicted in various cultures worldwide. They are commonly kept in captivity and are even sometimes trained to perform tricks and tasks. Once relentlessly hunted by commercial industries for their products, seals and walruses are now protected by international law. The Japanese sea lion and the Caribbean monk seal have become extinct in the past century, while the Mediterranean monk seal and Hawaiian monk seal are ranked endangered by the International Union for Conservation of Nature. Besides hunting, pinnipeds also face threats from accidental trapping, marine pollution, and conflicts with local people.

San Francisco Seals (baseball)

The San Francisco Seals were a minor league baseball team in San Francisco, California, that played in the Pacific Coast League from 1903 until 1957 before transferring to Phoenix, Arizona. They were named for the abundant California sea lion and harbor seal populations in the Bay Area. The 1909, 1922, 1925, and 1928 Seals were recognized as being among the 100 greatest minor league teams of all time.

Sea lion

Sea lions are sea mammals characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short, thick hair, and a big chest and belly. Together with the fur seals, they comprise the family Otariidae, eared seals, which contains six extant and one extinct species (the Japanese sea lion) in five genera. Their range extends from the subarctic to tropical waters of the global ocean in both the Northern and Southern Hemispheres, with the notable exception of the northern Atlantic Ocean. 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 8 ft (2.4 m) long, while the female sea lion weighs 100 kg (220 lb) and is 6 ft (1.8 m) long. The largest sea lion is Steller's sea lion, which can weigh 1,000 kg (2,200 lb) and grow to a length of 10 ft (3.0 m). Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight (about 15–35 lb (6.8–15.9 kg)) at a single feeding. Sea lions can go around 16 knots in water and at their fastest they can go up to 30 knots. Three species, the Australian sea lion, the Galápagos sea lion and the New Zealand sea lion are listed as Endangered.

Slippery the Sea Lion

Slippery the Sea Lion was a California sea lion (Zalophus californianus) who in June 1958 escaped from a marine mammal park in London, Ontario, Canada. The animal swam down the Thames to Lake St. Clair, and down the Detroit River to Lake Erie, finally being caught near Sandusky, Ohio by employees of the Toledo Zoo. The escape and subsequent sightings generated a considerable media frenzy, which was exploited by the owners of Storybook Gardens, the sea lion's home. Rumours persisted for decades that park employees had planned the escape as a publicity stunt. (A "custody dispute" staged by the Storybook and Toledo parks may have contributed to the impression.) He later died in January 1967.

Stripefin poacher

The Stripefin poacher (Xeneretmus ritteri) is a fish in the family Agonidae (poachers). It was described by Charles Henry Gilbert in 1915. It is a marine, deep water-dwelling fish which is known from the eastern central Pacific Ocean, including southern California, USA; Baja California, Mexico; and an isolated population in the Gulf of California. It dwells at a depth range of 183–366 metres, and inhabits soft benthic sediments. Males can reach a maximum total length of 16 centimetres.The Stripefin poacher is preyed on by the California sea lion.

The Marine Mammal Center

The Marine Mammal Center is a private, non-profit U.S. organization that was established in 1975 for the purpose of rescuing, rehabilitating, and releasing, marine mammals who are injured, ill, or abandoned. It was founded in Sausalito, California by Lloyd Smalley, Pat Arrigoni, and Paul Maxwell. Since 1975 they rescued over 20,000 marine mammals. It also serves as a center for environmental research and education regarding marine mammals, namely cetaceans (whales and dolphins) and pinnipeds (seals, fur seals, and sea lions). Marine mammal abandonment refers to maternal separation; pups that have been separated from their mother before weaning. At the center, they receive specialized veterinary care; diagnosed, treated, rehabilitated, and ideally, released back into the wild. Animals in need of assistance are usually identified by a member of the public who has contacted the center. These animals represent the following major species: California sea lion, northern elephant seal, Pacific harbor seal, northern fur seal, and the southern sea otter. On a few occasions, the Marine Mammal Center has taken in Guadeloupe fur seals, Steller sea lions, and bottlenose/Pacific white-sided dolphins. The only non-mammals that the center takes in are sea turtles.

Welsh Mountain Zoo

The Welsh Mountain Zoo, is a zoological garden located near the town of Colwyn Bay in Conwy County, Wales. The zoo was opened on 18 May 1963 by the wildlife enthusiast and naturalist Robert Jackson. The zoo covers an area of 37 acres (15 ha).

Zalophus

Zalophus is a genus of the family Otariidae (sea lions and fur seals) of order Carnivora. It includes these species, of which one became recently extinct:

Z. californianus: California sea lion

Z. japonicus: Japanese sea lion †

Z. wollebaeki: Galápagos sea lion

Extant Carnivora species

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