localized prey depletion from fishing or disturbance). Research activities have intensified as scientific findings, litigation, and new legislation focused increasing attention on the species’ population decline and concerns over possible impacts by commercial fisheries in Alaskan waters. Average standard length of males is 282 cm and of females 228 cm (maximum 325 and 290 cm, respectively). Steller sea lions also are found around the entire rim of the North Pacific Ocean, from central California to Japan. There are two recognized subspecies: western, PHOTOS: (CLOCKWISE FROM UPPER LEFT) M. MALLESON, M. NOLAN, V. SHORE, M. NOLAN, Glenn R. VanBlaricom, ... Robert L. Brownell, Glenn R. Van Blaricom, ... Robert L. Brownell, Encyclopedia of Biodiversity (Second Edition), Long-term Ecological Change in the Northern Gulf of Alaska, Data from the National Marine Mammal Laboratory, Seattle, WA. Steller Sea Lions may appear greyish white when wet. Updated from Bigg (1985) (, Data have been grouped and totalled into 5-year periods, and are colour-coded by major breeding area. Unfortunately, once an animal is entangled the potential for rescue or rehabilitation is extremely low, from both a technical and practical standpoint. 1984; Trites and Larkin 1996). Juveniles are darker than adults and are dark tan to light brown. Adult females with young pups feed extensively at night, switching to foraging at any time after the breeding season. Steller Sea Lions can climb steep rocks and are often found many metres above the sea surface;  they tend to be highly gregarious while on land and generally pack close together in dense breeding colonies (rookeries) or non-breeding haulouts (Schusterman 1981; Loughlin et al. These initiatives provide information on pinniped incidents, and provide capacity for response actions on a case-by-case basis. Stellers occasionally prey on juvenile fur seals. Last Update: 2015-05-25 Usage Frequency: 3 Quality: Reference: Wikipedia. 2007). In southern B.C., winter haulouts are often shared with subadult and adult male California sea lions (Zalophus californianus) (Hancock 1970; Brenton 1977; Bigg 1985). Outside of the summer breeding season, Steller Sea Lions use year-round haulouts as well as winter-haulouts that may be considerable distances from rookeries. Recent rulings in US federal courts have restricted fishing activity in some locations and seasons for the purpose of reducing the rate of decline, intensifying the associated political debate. Sightings at sea are most often of groups of 1–12 animals. Entanglement in Marine DebrisThe increasing prevalence of synthetic debris (net fragments, plastic bags and packing bands, etc.) Females begin returning to rookeries in late May and give birth to a single pup within a few days of their arrival; most pups are born by early July (Gentry 1970; Edie 1977; Bigg 1985). In marine mammals, density dependence is generally thought to be expressed primarily in the parameters that affect reproductive rates, especially of younger animals (i.e., age at first reproduction, fecundity rates, and juvenile survival) (Eberhardt 1985; Fowler 1987). Steller Sea Lions were not known to breed in SE Alaska during the early 1900s and were not subjected to major control programs. 2007), compared with approximately 45,000 Steller Sea Lions in western Alaska (Angliss and Outlaw 2007) and 16,000 in Asia (Burkanov and Loughlin 2007). Kuril Islands, Russia. (DFO 2008), it is unlikely that this threat currently impacts population viability (Table 1). Pups are born with a wavy, chocolate brown coat (Fig. Taxonomic information Carnivora, Otariidae. Targeted enforcement of disturbance is focusing on whale oriented viewing, but also addresses the disturbance of pinnipeds, especially when hauled out near populated areas. Steller Sea Lions in Canada and neighbouring waters were subjected to predator control programs during most of the 20th century. The direct and incidental killing of sea lions in the 1950s through the first half of the 1980s (described in Section 3.5) likely had effects on local abundances, but in the mid-1970s the Western Stock was considered to be at or near the pre-exploitation level of abundance (Interagency Task Group, 1978). Premature births were more common and pup production was somewhat lower in the year following the spill, but limited data prior to EVOS and the ongoing population decline in the area made it difficult to assess the statistical significance of the impact (Calkins et al. York (1994) using two age-structure samples with their estimated survival and fecundity rates and counts of Steller sea lions from aerial surveys suggested that the early decline was mostly caused by a decline in juvenile survival. Canada uses a management scheme referred to as “Objective Based Fisheries Management.” They have identified upper and lower reference points of 30 and 70% of the historical maximum population. Infected Steller sea lions can discharge feces contaminated with caliciviruses, and virus transmission can occur either directly or indirectly by intermediate or prey species in the tidal pools and kelp beds. In contrast to these trends in the Western Stock, the Eastern Stock in southeast Alaska, although historically much smaller than elsewhere, has been increasing at 1–2% per year over the past 40 years and now numbers about 20,000, the highest in recorded history (Fig. have been subsequently tracked up to 1,700 km, ranging north to Alaska or south to California (Calkins 1981; Fisher 1981; Loughlin, pers. 1995; Reijnders et al. They have recently been separated into three genetically distinct stocks: the Eastern Stock along the west coast of North America from California to southeastern Alaska; the Central Stock from Kayak Island west to the Commander Islands at the western end of the Aleutian Archipelago; and the Western Stock from the Commander Islands and western Bering Sea south to Japan (Bickham et al., 1996; Baker et al., 2005) (Fig. Steller Sea Lions can dive to depths of at least 310 m (Andrews 1999) and stay submerged for over 8 minutes (Swain and Calkins 1997), with most dives in the range of 15-50 m and lasting 1.5-2.5 min (Merrick and Loughlin 1997; Swain and Calkins 1997; Loughlin et al. A small group of young and older western Steller sea lion pups interacting. However, a spill affecting a rookery during the breeding season could result in a significant population-level impact. The cause or causes of long-term decline in the western population of Steller's sea lions are not understood. The diving of adult males has not been studied. Commercial harvesting can deplete local abundance and availability of prey (Lowe and Fritz 1997; Fritz and Brown 2005), and harvesting surplus production on a continual basis could affect resilience and amplify the effects of natural prey fluctuations. Asterisk (*) denotes naturally occurring threats to the population (i.e. Permanent populations remain spotted up the coasts of California (Farallon Islands), Oregon (Rogue Reef), Washington, Canada, and Alaska, then east along the Aleutian Island chain and onto the Pribilof Islands (Fig. Total abundance in the United States and Russia of this subspecies was estimated to be 78,000 in 2011. English. comm. More than 50% of the articles were written since 2004 with the majority pertaining to Steller sea lion life history, foraging ecology and vital rates. California sea lions are the most likely species to be confused with Steller sea lions. The Steller sea lions’ range overlaps with the California sea lion (Zalophus californianus), but these two species are easily distinguished; the latter is darker and smaller. Also, smaller Steller sea lions have little or no sagittal crest development and a nearly flat-topped head, whereas comparably-sized adult and subadult male California sea lions have a moderate to large sagittal crest and more pronounced forehead. The first digit is the longest, widest and thickest, and curves posteriorly, giving the flipper a swept back look. 2007). Adult male Loughlin’s Steller sea lion next to a fairly large adult male California sea lion. An additional 90,000 are taken by Greenland from the same population. However, proactive measures including siting of aquaculture operations away from haulouts, gear modification (both fisheries and aquaculture), and all reasonable non-lethal means of control at aquaculture sites, to minimize risks of entanglement or entrapment is being used. Also, smaller Stellers have little or no sagittal crest development and a nearly flat-topped head whereas comparably-sized adult and subadult California sea lion males have a moderate to large sagittal crest and more pronounced forehead. Additionally, an increasing trend in population growth for Transient Killer Whales (Ford et al. 1995). Some First Nations names for sea lion include; tukuk or tukukw (tukwašt meaning dried sea lion) in Nuu-chah-nulth Barkley Sound dialects (BSDWG 2004), in Kwakiutl sea lion are referred to as tl’íx7en (Grubb 1977), and in the Haida language, kíit or kíidaay (Lawrence 1977). Anthropogenic threats affecting sea lions in North America that require further clarification include: 1 Regulated and unregulated contaminants of concern are listed in Appendix II.2 The vast number of pinniped entanglements (110 out of 170) can be attributed to shark guards used at one site, and these have since been removed (DFO unpublished data). This weight of evidence regarding effects and persistence of regulated and unregulated pollutants on Steller Sea Lions leaves concern for effects to the population viability. Steller Sea Lions also congregate in estuaries during autumn to feed on pre-spawning salmon and at the mouth of the Fraser River in spring when Eulachon are running (Bigg 1985; Bigg et al. Harvest ControlsThe conservation and management of Steller Sea Lions in Canada falls under the authority of the Fisheries Act (1985), more specifically the Marine Mammal Regulations (1993) of that Act. and southeast Alaska, as the largest breeding aggregation of Steller Sea Lions on Forrester Island is situated less than 50 km north of the international border. Toxic SpillsSea lions may be impacted by catastrophic accidents such as toxic spills (St. Aubin 1990), although the impact on a population-wide scale has rarely been established. The magnification of such chemicals with increasing position in the food web predisposes many marine mammals to becoming highly contaminated. As mentioned in ‘Limiting Factors’, climate change and large-scale regime shifts can affect biota throughout the North Pacific (Sinclair et al. Most territorial males are 9-13 years old (Thorsteinson and Lensink 1962) and may hold a territory for several years in succession (range 1-7 years) (Gisiner 1985). The ratio of pups to non-pups provides an index of relative birth and survival rates. This subadult male Loughlin’s Steller sea lion was branded as a pup for re-identification in long-term studies. Two hundred or more may be taken a year in Alaska. Steller’s sea lion (also known as the northern sea lion) lives along the rocky coasts of the North Pacific, with a range extending from California to Canada, Alaska, the Bering Strait, Kamchatka and on to northern Japan.It is the largest of all sea lion species.Adult males are 3 metres long and can weigh up to a tonne, while females are smaller and much lighter. (modified from Bigg 1985 and Olesiuk et al. Parler aux habitants de Reflet-de-Lune pour obtenir des indices quant à l’endroit où ces objets se trouvent.Reformer le Pendentif du lion de mer à partir des deux moitiés. (modified from Loughlin 1997 and Sease et al. Increases in ocean temperatures resulting from global climate change might be expected to shift the distribution of Steller Sea Lions northward (NMFS 2008), and indeed the species has been disappearing from the southernmost part of their breeding range on both the North American and Asian coasts (Pitcher et al. Thomas A. Jefferson, ... Robert L. Pitman, in Marine Mammals of the World (Second Edition), 2015. The scientific name (Eumetopias jubatus) means having a broad forehead and a mane, a reference to the prominent ruff of coarse hair that mature males develop on their necks and chests, from which is also derived the name ‘lion’. Regime Shift)*, Un-regulated Persistent Organic Pollutants (POPs), Physical disturbance when on terrestrial habitat, Acoustic disturbance when in aquatic habitat, Habitat use (i.e.

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