STELLER SEA LION (Eumetopias jubatus)

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1 STELLER SEA LION (Eumetopias jubatus) Status ESA Endangered - Western Distinct Population Segment ESA Threatened - Eastern Distinct Population Segment MMPA Depleted - throughout its range

2 Fast Fun Facts Did You Know? Steller sea lions' impressive low-frequency vocalizations sound more like a "roar" when compared to California sea lions, which sound more like a "bark." The scientific name, Eumetopias jubatus, comes from the Greek words "eu" and "metopion" for "typical/well" and "broad forehead," and the Latin word jubatus for "having a mane." Steller sea lions are named for the German surgeon and naturalist George Wilhelm Steller. In 1742, he observed and described these large pinnipeds. Steller sea lions are the fourth largest pinniped in the world, behind the northern elephant seal, southern elephant seal, and walrus.

3 Taxonomy Kingdom: Animalia; Phylum: Chordata; Class: Mammalia; Order: Carnivora; Family: Otariidae; Genus: Eumetopias; Species: jubatus Species Description Weight: males: up to 2,500 lbs (1,120 kg) females: up to 770 lbs (350 kg) pups: about lbs ( kg) Length: males: about ft (3-3.4 m) females: about ft ( m) pups: about 3.3 ft (1 m) Appearance: adults: light blonde to reddish brown and slightly darker on the chest and abdomen; pups: dark brown to black. The light colo ration is still visible when the body is wet, which is different from many pinniped species. Like other pinnipeds, their coat of fur "molts" every year. Both sexes also have long whitish whiskers, or vibrissae, on their muzzle. The flippers and other hairless parts of the skin are b lack. The fore-flippers are broader and longer than the hind-flippers and are the primary means of locomotion in water. On land, sea lions, unlike "true" seals, can turn their hind flippers forward for walking. Lifespan: years Diet: variety of fishes (capelin, cod, herring, mackerel, pollock, rockfish, salmon, sand lance, etc.), bivalves, squid, octopus, and gastropods Behavior: use land habitat as haul-out sites for periods of rest, molting, and as rookeries for mating and pupping; colonial breeders, adult males ("bulls") establish and defend territories on rookeries to mate. They are capable of powerful vocalizations that are accompa nied by a vertical head bobbing motion by males. Adult males, also known as bulls, establish and defend territories on rookeries to mate with females. Bulls become sexually mature between 3 and 8 years of age, but typically are not large enough to hold territory successfully until 9 or 10 years old. Mature males may g o without eating for 1-2 months while they are aggressively defending their territory. Females typically reproduce for the first time at 4 to 6 years of age, usually giving birth to a single pup each year. Adult females, also known as cows, stay with their pups for a few days after birth before beginning a regular routine of alte rnating foraging trips at sea with nursing their pups on land. Female Steller sea lions use smell and distinct vocalizations to recognize and create strong social bonds with their newborn pups. Pups have a dark brown to black "lanugo" coat until 4 to 6 months old, when they molt to a lighter brown. By the end of their second year, pups are on the same color as adults. Females usually mate again with males within 2 weeks after giving birth. Males can live to be up to 20 years old, while females can live to be 30.

4 -On average, nose-to-tail length of 3 m and weight about 680 kg (1496 lbs). Weighing up to 1000 kg (2200 lbs); have a thick neck and big chest. -Males hold territories for an average of two years. -Males are much larger in appearance and overall size than females. -Male Steller sea lions have a thick mane to protect themselves when fighting with other males or from the cold temperatures & from jagged rocks. -Males have a higher mortality rate than females, by ten years of age there is a 3:1 ratio of females to males. -Males are 1.3 times as long and 2.5 times as heavy as females. -Adult males lose weight & grow little during the summer breeding season while fasting. -Adult males gain weight from autumn through early spring in preparation for the breeding season. -Length of 2.3 m and weigh about 270 kg (594 lbs). -Lighter coat than pups. -Slimmer neck than males. -Arrive at rookeries shortly after the males and give birth to a single pup each year, within three days of being on land. -Females usually mate about two weeks after pupping. -Weigh about 20 kg (44 lbs) when born (male pups are usually larger than female pups). -Brown or chocolate coat. -Pups are born from late May to early June. -Juvenile animals may also grow very little during the breeding season and summer, with most of their growth occurring from autumn to spring. -Pups generally nurse for a year and may stay with their mother for up to three years (considered immature at this point). There is considerable uncertainty about when sea lion pups are weaned.

5 Adult Male has thick mane and robust chest Very large body size separates it from other age and sex classes Sub-adult Males will have slightly less size and no pronounced mane Adult Male with Adult Female and newborn Pup

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7 Sub-Adult Males are larger than adult females but smaller than adult males They lack the full mane seen on adult males but possess a thicker neck than adult females Sub-adult male surrounded by California Sea Lions. Notice no mane but thickened neck.

8 Adult Females are generally blonde in most of pelage with obvious color change to dark or chocolate brown on flippers (good way to distinguish between California Sea Lions although light colored CSL are somewhat common) Adult Females can also be distinguished by broad fore flippers and larger bear-like head SSL do not bark like CSL but rather let out a long deep belching sound Branded Adult Female with newborn pup

9 Immatures are most often confused with adult females because of similar body size Immatures can sometimes be seen nursing from adult females if she has not yet produced the current year s pup Look for behavior as a way to distinguish immatures from adult females as immatures will tend to be more playful and wander around when hauled out where as adult females spend most of their time sleeping when out of water. Mixed adult females and immatures Adult Female Notice slight size difference in body and head with immatures being smaller than adult females Immature

10 Adult Female with pup Pups are obvious and will be seen on SEFI starting in June and are considered pups until they reach 1 yr (in which they become immatures by SEFI standards Fuzzy lanugo apparent on pup

11 Habitat Steller sea lions prefer the colder temperate to sub-arctic waters of the North Pacific Ocean. Haul outs and rookeries usually consist of beaches (gravel, rocky or sand), ledges, rocky reefs. In the Bering Sea and Okhotsk Sea, sea lions may also haul out on sea i ce, but this is considered atypical behavior. Critical habitat has been defined for Steller sea lions as a 20 nautical mile buffer around all major haul-outs and rookeries, as well as associated terrestrial, air and aquatic zones, and three large offshore foraging areas (50 CFR on Aug. 27, 1993). Distribution Steller sea lions are distributed mainly around the coasts to the outer continental shelf along the North Pacific Ocean rim from nort hern Hokkaiddo, Japan through the Kuril Islands and Okhotsk Sea, Aleutian Islands and central Bering Sea, southern coast of Alaska and south to California. The population is divided into the Western and the Eastern "distinct population segments" (DPSs) at 144 West longitude (Cape Suckling, Alaska). The Western DPS includes Steller sea lions that reside in the central and western Gulf of Alaska, Aleutian Islands, as well as those that inhabit the coastal waters and breed in Asia (e.g., Japan and Russia). The Eastern DP S includes sea lions living in southeast Alaska, British Columbia, California, and Oregon. Population Trends For management purposes, Steller sea lions inhabiting U.S. waters have been divided into two DPSs: the Western U.S. and the Eastern U.S. The differentiation is based primarily on genetic and physical differences, but also on differing population trends in t he two regions. There are approximately 39,000-45,000 Steller sea lions in the Western U.S. and 44,500-48,000 in the Eastern U.S. The Western DPS declined by 75% between 1976 and 1990, and decreased another 40% between 1991 and 2000 (the average annual decline during this period was 5.4%). Since the 1970s, the most significant drop in numbers occurred in the eastern Aleutian Islands and the western Gulf of Alaska. The extent of this decline led NMFS to list the Steller's sea lion as threatened range-wide under the Endangered Species Act (ESA) in April In the 1990s, the decline continued in the Western portions of the range leading NMFS to divide the species into two distinct population segments (DPS), Western and Eastern, and list the Western DPS as endangered i n Population surveys suggest that the Eastern U.S. DPS is stable or increasing in the northern part of its range (Southeast Ala skan and British Columbia), while the remainder of the Eastern DPS and all the Western DPS is declining.

12 Steller Sea Lion Distribution Steller sea lions range from southern California, around the Pacific rim to northern Japan, but most of the world's Steller population breeds between the central Gulf of Alaska and the western Aleutians.

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15 Steller Sea Lion Diet Steller sea lions eat a wide range of fish, but also consume cephalopods, crustaceans, birds and occasionally other pinnipeds. Analysis of sea lion feces has indicated that the major prey species during the 1990s were walleye pollock, Atka mackerel, salmon, Pacific cod, herring, arrowtooth flounder, cephalopods, rockfish and sandlance. Diet appears to vary between regions and has also changed through time (see changes in diet). The causes and consequences of these changes are still under debate (see ecosystem change and over-fishing). Feeding Patterns Sea lions often feed in groups and tend to feed at night between 9 PM and 6 AM. Feeding in groups may help to control the movement of large schools of fish and make them easier to exploit. Sea lions may feed close to shore or may travel 100 or more miles (>150 km) out to sea. Stomach samples and feces (scat) samples indicate sea lions prey upon a wide selection of fishes including capelin, sandlance, pollock, herring, cod, salmon, flatfishes, sculpins, squid, octopus and occasionally seal pups. Most fish are swallowed whole. Large prey are torn apart and consumed at the surface. Food requirements of adult sea lions are believed to be between 5-6% of their body weight per day. Steller sea lions forage near shore and pelagic waters. They are also capable of traveling long distances in a season and can dive to approximately 1300 ft (400 m) in depth. At sea, they are seen alone or in small groups, but may gather in large "rafts" at the surface near rookeries and haul outs.

16 Threats Threats to Steller sea lions include: boat/ ship strikes contaminants/ pollutants habitat degradation illegal hunting/ shooting offshore oil and gas exploration interactions (direct and indirect) with fisheries Direct fishing impacts are largely due to fishing gear (drift and set gillnets, longlines, trawls, etc.) that has the potential to entangle, hook, injure, or kill sea lions. They have been seen entangled in fishing equipment with what are considered "serious injuries." Indirect fisheries impacts include having to compete for food resources and possible modifications to critical habitat by fis hing activities Historically, threats included: hunting for their meat, fur hides, oil, and various other products (in the 1800s) killing and placing bounties on this species, which fishermen blamed for stealing fish from them (in the early 1900s) killing to limit their predation on fish in aquaculture facilities (fish farms), but intentional killing of Steller sea lions has not been permitted since they were protected under the Marine Mammal Protection Act (MMPA) and listed under the ESA (not since 1972) Conservation Efforts Protective zones, catch/harvest limits, various procedures and other measures have been implemented around major haul -outs and rookeries in order to safeguard their critical habitat. The IUCN Red List of Threatened Species considers this species to be "Endangered." Subsistence harvests by natives in Alaska and Canada ( taken a year) also occur. Regulatory Overview The Steller sea lion was listed under the ESA as threatened throughout its range on December 4, This listing included animals from Alaska, California, Oregon and Washington in the U.S., as well as Canada, Japan, and Russia. On June 4, 1997, the population west of 144 W longitude was listed as an endangered DPS (the Western DPS) under the ESA; the population east of 144 W remained listed as threatened as the Eastern DPS. Under the MMPA, all Steller sea lions are classified as "strategic stocks" and are considered "depleted". Critical habitat has been designated (50 CFR on Aug. 27, 1993) for Steller sea lions as a 20 nautical mile buffer around all major haul-outs and rookeries, as well as associated terrestrial, air, and aquatic zones, and three large offshore foraging areas. NMFS has a lso designated no-entry zones around rookeries (50 CFR ). NMFS has implemented a complex suite of fishery management measures designed to mini mize competition between fishing and the endangered population of Steller sea lions in critical habitat areas. A recovery plan was developed for Steller sea lions in A revised recovery plan, which discusses separate recovery actions for the threatened and endangered populations, was issued in 2008.

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