2002). 2000; NMFS 2001; Gallucci et al. rookeries, although increasing numbers of animals have recently begun breeding on the gravel beaches along the eastern (leeward) side of Triangle Island (Olesiuk, unpublished data). The main threat is likely through contact with heavy oil accumulations when the source of the spill is near important habitats such as rookeries and haulout sites, and to a lesser degree from absorption through the skin, incidental ingestion of oil directly or through feeding, exposure to vapours, and partial fouling of pelage from fresh oil (Smith and Geraci 1975; Engelhardt et al. These studies have provided over 750 primary citations, journal articles, progress and technical reports, contract reports, proceedings of conferences and symposia, books, thesis and other manuscripts. cited in Angliss and Outlaw 2007). Pups are born with a wavy, chocolate brown coat (Fig. The pale adult female Loughlin’s Steller sea lions are as large as the dark adult male California sea lions. 1996; Melin and DeLong 2000). aerial surveys indicate that numbers of pups and non-pups on rookeries increased at a mean rate of 3.5% and 3.9% per annum respectively, which has resulted in a tripling in the size of the breeding population since the early 1970s (Figure 5) (DFO 2008). Figure 4: Total Numbers of Steller Sea Lions Reported to have been Killed in B.C. 2007), resulting in population decline. These documents include recommended actions for recovery, protection and management of listed marine mammal species. The effects of threats and limiting factors can be difficult to distinguish from one another, making conclusions regarding causes of population decline often difficult to ascertain. Steller sea lion distribution (in yellow) in the North Pacific Ocean. comm.). Regime Shift)*, Un-regulated Persistent Organic Pollutants (POPs), Physical disturbance when on terrestrial habitat, Acoustic disturbance when in aquatic habitat, Habitat use (i.e. The Steller sea lion, also known as the Steller's sea lion and northern sea lion, is a near-threatened species of sea lion in the northern Pacific. Steller sea lions can leave haulouts in large groups. Adult males arrive at the rookeries before females, and those that are nine years or older, fight for and often obtain a territory, which they aggressively and vociferously defend. The species is gregarious while on land, and animals gather at traditional rookeries and haulout sites, some of which have been used for over a century. The same local-scale variance in trend is known for the eastern population. Due to the recent declines in Alaska, the British Columbia rookeries at the Scott Islands and Cape St. James now represent the second and sixth largest breeding aggregations in the world. Large sharks may also prey on Steller Sea Lions in the southern part of their range (Stroud 1978; Ainley et al. Crabs, mussels, clams and other invertebrates are occasionally recovered in stomachs and scats, but these may represent secondary prey that had been consumed by the prey species eaten by sea lions. In addition to fish, squid and octopus are sometimes consumed, but their importance was likely exaggerated in earlier studies because cephalopod beaks likely accumulate in stomachs over extended periods (Bigg and Fawcett 1985). Further genetic samples of the population within B.C. During the control programs conducted prior to 1970, some breeding animals were likely displaced to other rookeries, but the majority of sea lions continued to return to sites that had been heavily disturbed for many consecutive years. They once bred in the Channel Islands, but are now rarely seen south of Monterey Bay. The severity of a population-wide impact on Steller Sea Lions as a result of entanglement in marine debris is unknown, however as entanglements have been recorded, it is evident that this threat affects some proportion of the population. Taxonomic information Carnivora, Otariidae. There are two recognized subspecies: western Steller sea lion (E. j. jubatus), and Loughlin’s Steller sea lion (E. j. monteriensis), as recently adopted by the Society for Marine Mammalogy. 2007) indicates that there is potential for the predation rate to increase. 1999; Pitcher et al. 2007). Mitigation potential refers to the likelihood that measures (future or existing) may mitigate or prevent negative effects to the population. The rate of decline has varied over time, with the highest rates (approximately 15% per year) from 1985 until 1990. Visit. 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). Protection of HabitatThe Fisheries Act (ss. 1997; Anderson and Piatt 1999; Hare et al. Pups are born from May through July, and females stay continuously ashore with their newborns for the first week to ten days after giving birth. California sea lions are the most likely species to be confused with Steller sea lions. These data could be seen to indicate that whatever occurred was initiated early in life and resulted in “stunting” during the first year, and this overall event had been an annual occurrence for 10 years. Steller Sea Lion are known to feed on a variety of prey species, and it is not known whether limitations in one prey species alone may limit population growth. L'eider de Steller est classé «vulnérable» par l'UICN et figure à l'annexe 1 de la directive «Oiseaux» de l'UE, comme le plongeon catmarin, le plongeur arctique, le grèbe esclavon et le harle piette. Increasing knowledge of the seasonal distribution of Transient Killer Whales and their diet will assist in determining the degree to which predation regulates Steller sea lion population growth in B.C. The renegotiated Treaty of 1957 provided a vehicle for cooperative research among scientists of the party nations and specified that the population was to be managed to obtain “maximum sustained productivity.” Attempts were made to fit spawner-recruit models to fur seal data and to use them to set the harvest, but these methods largely failed, probably due to high variability in year class survival. There is a small opening in the skin at the end of each digit for a claw that is usually reduced to a vestigial nodule, and rarely emerges above the skin. The 12 in British Columbia at the Vancouver Aquarium and 3 at the Alaska SeaLife Center in Alaska are held for both research and exhibit. Fisheries and Oceans Canada, Conservation and Protection Branch responds to, as necessary, and investigates reports of unauthorized lethal take (including attempts) and disturbance to all marine mammals, in the course of general operations. Longues et larges, ses nageoires pectorales lui permettent de se diriger sous l'… coast has increased the number and frequency of visits to haulout areas. This subadult male Loughlin’s Steller sea lion was branded as a pup for re-identification in long-term studies. Adult male Loughlin’s Steller sea lion next to a fairly large adult male California sea lion. (a) Trends in Steller sea lion populations in the central and western GOA (blue) and the northeastern GOA (red). Thomas A. Jefferson, ... Robert L. Pitman, in Marine Mammals of the World, 2008. 2002; Pitcher et al. As a population-wide impact has been illustrated to be unlikely, concern for catastrophic spills affecting the population has been rated low (Table 1). 1983; Loughlin and DeLong 1983; P. Olesiuk, Fisheries and Oceans Canada – Pacific Region, Science, pers. Steller sea lions feed on a wide variety of small schooling fish but also take numerous species a of larger prey as shown here, clockwise from upper left: octopus, halibut, shark, and salmon. Sewage outflow, storm-water and agricultural runoff may play important roles as vectors for pathogens or disease, as do multi-species rehabilitation-reintroduction programs that include pinnipeds. Commercial fisheries target on several of the most important prey eaten by Steller sea lions. 1996; Melin and DeLong 2000). Adult males are known to occasionally kill and consume young northern fur seals, harbor seals, and in one case, a juvenile California sea lion. and neighbouring waters have now recovered past historic high levels, natural population regulatory mechanisms might become a factor governing the status of Steller Sea Lion populations. 2002). The population decline in the Aleutian Is. Last Update: 2015-05-25 Usage Frequency: 3 Quality: Reference: Wikipedia. 1975. It is unknown whether subsistence harvesting prior to the 1900s regulated the Steller Sea Lion population in B.C. As populations continue to grow, and prey requirements increase, Steller Sea Lions may become more susceptible to prey shortages. (2007) estimated that killer whales consumed 3-7% of the Steller Sea Lion population in Kenai Fjords annually, and 11% of pups born at their main study site on Chiswell Island, which could be significant for a species with such an inherently low rate of productivity. The needs of Steller Sea Lions can be partitioned between the time they spend on land when they come ashore to rest and reproduce, and the time they spend at sea where they travel and forage. 1998; Pitcher et al. Impacts on other killer whale prey, such as harbour seals, could result in a shift in killer whale diet and increased predation on sea lions. 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. Possible risk factors include incidental take in fishing gear, competition with fisheries for prey in common, hunting by indigenous peoples, illegal hunting or harassment, inadvertent rookery disturbance, consumption by killer whales, disease or parasitism, contaminants, and changes in the structure and productivity in the marine ecosystems of which Steller's sea lions are part. About 70 percent of the Steller sea lion population resides in Alaska. Diversity of the diet in the increasing Eastern Population appears to be high (Trites et al. Because of these dynamics and the very long south-to-north and warm-to-cold-water distribution of the Steller range and the lack of long-distance migration cycles, certain discrete or local colonies and herds have been unequally affected. In comparison, the total annual commercial fish landing in B.C. Proposed amendments to these regulations would also provide specific protection from some forms of disturbance such as swimming with, or feeding marine mammals. Prior to the species being protected in the 1970s, the Canadian government conducted intensive culls of Steller Sea Lions at rookeries, for the mandated purpose of protecting salmon fisheries (Figure 4). The principle cause of death for pups is drowning due to limited swimming abilities at this age preventing them from hauling out of the water or steering in strong tidal currents (Orr and Poulter 1967; Edie 1977). This suggests there are also other sources of mortality for these sea lions. Of particular uncertainty is their diet outside of the breeding season. Steller sea lions hauled-out on sea ice in the Karaginsky Gulf, Russia. The Steller Sea Lion is the largest member of the eared seals, or sea lions and fur seals (Order Carnivora, Superfamily Pinnipedia, Family Otariidae; Rice 1998). Steller sea lions suffered a significant decline in the western area of their U.S. range from the late 1970s through the 1980s (Braham et al. All are currently managed to prescribed catch levels, which are believed to be sustainable. 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. All sea lions are remarkably agile on land due to their ability to rotate their hind flippers forward and prop themselves up on their foreflippers. 1999). Abundance in Canadian waters was estimated to be 20,000-28,000 based on the most recent survey in 2006 (DFO 2008). and consume the same prey species (Olesiuk and Bigg 1988). As has been shown in other marine mammals, contaminant concentrations in Steller Sea Lions (predominantly organochlorines) are linked to age and gender. Basic knowledge of seasonal and regional feeding habits of sea lions in B.C. The vernacular name for this subspecies is Loughlin’s northern sea lion. The potential for mitigation of this threat is high (Table 1) as fisheries extractions may be managed directly through Fisheries and Oceans Canada. Steller Sea Lions forage on a variety of prey items, primarily small or medium-sized schooling fish, and foraging habitat varies in relation to prey distribution and abundance. Common Name (population): Steller Sea LionScientific Name: Eumetopias jubatus, Reason for Designation: There are only three1 breeding locations in British Columbia. Recovering Steller Sea Lion populations along the west coast of North America have sustained growth recovery rates of only about 3.1% per annum and have exhibited no signs of density dependence as populations increased, but it is not known whether this represents the maximum intrinsic rate of increase for the species or whether some stressor has been inhibiting recovery throughout this region for the past 40 years (Pitcher et al. For females, these daily energy requirements represent about 14% of body weight for a 1 year old and 7% for a mature individual. Information on key vital rates of Steller Sea Lions are required to determine age and sex specific fecundity and survival rates, age at weaning, and age of first reproduction that regulate population productivity. Average weight of males is 566 kg and of females 263 kg (maximum 1120 and 350 kg, respectively).