Eumetopias jubatus - (Schreber, 1776)
Steller Sea Lion
Other English Common Names: Northern Sea Lion, Steller Sea-lion
Synonym(s): Phoca jubata
Taxonomic Status: Accepted
Related ITIS Name(s): Eumetopias jubatus (Schreber, 1776) (TSN 180625)
French Common Names: otarie de Steller
Unique Identifier: ELEMENT_GLOBAL.2.104433
Element Code: AMAJC03010
Informal Taxonomy: Animals, Vertebrates - Mammals - Carnivores
Image 11470

© Larry Master

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Mammalia Carnivora Otariidae Eumetopias
Genus Size: A - Monotypic genus
Check this box to expand all report sections:
Concept Reference
Help
Concept Reference: Wilson, D. E., and D. M. Reeder (editors). 1993. Mammal species of the world: a taxonomic and geographic reference. Second edition. Smithsonian Institution Press, Washington, DC. xviii + 1206 pp. Available online at: http://www.nmnh.si.edu/msw/.
Concept Reference Code: B93WIL01NAUS
Name Used in Concept Reference: Eumetopias jubatus
Taxonomic Comments: No controversy exists regarding the taxonomic status of this species. Research has focused on identifying patterns of genetic variation within the species. Some of this research is summarized here.

MtDNA data of Bickham et al. (1996) indicated the existence of two genetically differentiated populations of E. jubatus, one in the Commander Islands in Russia and the Aleutian Islands and Gulf of Alaska in Alaska, the other including samples from southeastern Alaska and Oregon; the populations do not trace their ancestries back to a single maternal ancestor in either case; they likely diverged as a result of separation in different glacial refugia. The authors stated that the two populations "likely should be managed separately."

Trujillo et al. (2004) studied genetic variation at 6 nuclear microsatellite loci with biparental inheritance and the maternally inherited mitochondrial DNA (mtDNA) at 3 geographic scales (rookeries, regions, and stocks). Population structure was not well defined, and there was no obvious phylogeographic pattern to the distribution of microsatellite alleles. This contrasts with the clear phylogeographic pattern revealed by control-region sequences of mtDNA in which 2 well-differentiated stocks, eastern and western, were defined as well as 2 distinct groups, Asian and central, in the western stock. Trujillo et al. (2004) stated that the difference in patterns between the biparentally and maternally inherited genetic markers can be explained by relatively high male dispersal rates and female philopatry, or else there has been insufficient time since populations have been isolated for the nuclear loci to have diverged. Trujillo et al. (2004) recommended that the presently accepted stock structure be retained for management purposes and that further studies be carried out to test the male dispersal hypothesis.

Harlin-Cognato et al. (2006) examined Steller sea lion phylogeography using range-wide mtDNA data and found that the pattern of diversification of female lineages appears to correlate with the glacial advances and retreats during the Pleistocene, from approximately 60,000 to 180,000 years ago. Four populations, ostensibly derived from distinct glacial refugia, were recognized, including continental North America, Gulf of Alaska and mainland Alaska, Aleutian Islands, and Eurasia.

Recent research indicates that the geographic boundary between the western and eastern populations may be changing or possibly disappearing (Pitcher et al. 2007; NMFS unpublished data, cited by NMFS 2008).

The English name for sea lions has been inconsistently rendered as sea lion, sealion, and sea-lion (Rice 1998; Wozencraft, in Wilson and Reeder 2005).
Conservation Status
Help

NatureServe Status

Global Status: G3
Global Status Last Reviewed: 04Apr2016
Global Status Last Changed: 18Nov1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G3 - Vulnerable
Reasons: Fairly large breeding range around the edge of the North Pacific; abundance declined greatly in the 1970s and 1980s, then declined at a lower rate in the 1990s, especially in the western segment of the range; subsequently the decline greatly decreased or ceased; population fluctuations may be related to competition with fisheries, environmental variability, toxic substances, predation by orcas (killer whales), or other factors, but further study is needed.
Nation: United States
National Status: N3 (15Jan1997)
Nation: Canada
National Status: N3 (01Jan2018)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alaska (S3), California (S2), Oregon (S2), Washington (S3N)
Canada British Columbia (S3B,S4N)

Other Statuses

Implied Status under the U.S. Endangered Species Act (USESA): PS:LE
Comments on USESA: Status as of July 2014:

Endangered - Western Distinct Population Segment
Delisted - Eastern Distinct Population Segment


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 DPS includes sea lions living in southeast Alaska, British Columbia, California, and Oregon.

Canadian Species at Risk Act (SARA) Schedule 1/Annexe 1 Status: SC (14Jul2005)
Committee on the Status of Endangered Wildlife in Canada (COSEWIC): Special Concern (01Nov2013)
Comments on COSEWIC: Reason for designation: This species is restricted to only five breeding locations (consisting of 7 rookeries) in British Columbia that occupy less than 10 kmē, with approximately 70% of births occurring at a single location (Scott Islands). The population is increasing, but is sensitive to human disturbance while on land and is vulnerable to catastrophic events such as major oil spills due to its highly concentrated breeding aggregations. The species is near to qualifying for Threatened, but has recovered from historical culling and deliberate persecution.

Status history: Designated Not at Risk in April 1987. Status re-examined and designated Special Concern in November 2003 and November 2013.

IUCN Red List Category: NT - Near threatened

NatureServe Global Conservation Status Factors

Range Extent: >2,500,000 square km (greater than 1,000,000 square miles)
Range Extent Comments: Range includes coastal waters of the North Pacific Ocean from California and northern Honshu, Japan, and Korea, north to the Bering Strait (Kenyon and Rice 1961, Calkins and Pitcher 1983, Loughlin et al. 1984, Bigg 1988, Perlov 1991, Sea Lion Recovery Plan Team 1991, NMFS 2008). NMFS (2008) divides the population into eastern and western distinct population segments at 144° west longitude (Cape Suckling, Alaska).

Breeding rookeries extend from the central Kuril Islands and the Okhotsk Sea in the west to Aņo Nuevo Island and (formerly) San Miguel Island, California, in the east (Loughlin et al. 1987; NMFS 1993, 2008). Most of the largest rookeries formerly were in the Gulf of Alaska and the Aleutian Islands (Loughlin et al. 1984), but with the decline in the western distinct population segment the largest rookeries are now in Southeast Alaska and British Columbia (NMFS 2008). Breeding colonies occur in Oregon and British Columbia but not in Washington (nonbreeding occurrences only, mainly October to April).

Area of Occupancy: 126-2,500 4-km2 grid cells
Area of Occupancy Comments: The area of occupancy based on breeding rookeries is vastly smaller than the overall range extent. Based on the 2 km x 2 km grid system and assuming 65 major rookeries each of which is represent by one grid cell, the area of occupnacy for breeding would be only 260 square kilometers.

Number of Occurrences: 21 - 80
Number of Occurrences Comments: NMFS (2008) mapped approximately 65 breeding rookeries (sites where greater than 50 pups were born); 13 of these are in the eastern distinct population segment. There are several hundred haul-out sites (NMFS 1993).

Population Size: 100,000 - 1,000,000 individuals
Population Size Comments: In the late 1970s, total population estimates had remained stable at about 250,000-300,000 since the late 1950s, with breeders distributed among 51 rookeries, 60 percent of which included over 1,000 adults; 38 percent of the recorded population was at nonbreeding haul-out sites during the breeding season (Loughlin et al. 1984). Surveys at rookeries and haulout sites throughout Alaska and Russia in 1989, and estimates from counts conducted at other locations in recent years, provided the following minimum numbers of sea lions: Alaska (53,000); Washington, Oregon, California (4,000); British Columbia (6,000); Russia (3,000) (National Marine Fisheries Service 1990).

Based on 2004-2005 data (NMFS 2008), the total population size of the western distinct population segment (DPS) of Steller sea lions in Alaska was estimated to be approximately 45,000 animals. The 2005 population of Steller sea lions in Russia (part of the western DPS) is estimated to be about 16,000. The eastern DPS was estimated to number between 46,000 and 58,000 animals in 2002 (Pitcher et al. 2007).

Overall Threat Impact: High
Overall Threat Impact Comments: Western distinct population segment (DPS): A threats assessment concluded that the following threats are relatively minor: (1) Alaska Native subsistence harvest, (2) illegal shooting, (3) entanglement in marine debris, (4) disease, and (5) disturbance from vessel traffic and scientific research. Considerable uncertainty remains about the following potential threats to the recovery of the western DPS (relative impacts in parenthesis): competition with fisheries (potentially high), environmental variability (potentially high), incidental take by fisheries (low), toxic substances (medium) and predation by killer whales (potentially high). Considerable uncertainty, controversy, and disagreement exist within the scientific and stakeholder communities with regard to the potential threat posed by killer whale predation. [Source: NMFS 2008]

Eastern DPS: No threats to continued recovery were identified by NMFS (2008) for the eastern DPS. Although several factors affecting the western DPS also affect the eastern DPS (e.g., environmental variability, killer whale predation, toxic substances, disturbance, shooting), these threats do not appear to be at a level sufficient to keep this population from continuing to recover, given the long term sustained growth of the population as a whole. However, concerns exist regarding global climate change and the potential for the southern part of the range (i.e., California) to be adversely affected. [Source: NMFS 2008]

Short-term Trend: Relatively Stable (<=10% change)
Short-term Trend Comments: Through the 1990s, the western distinct population segment (DPS) continued to decline. The western population showed an increase of approximately 3% per year between 2000 and 2004. This was the first recorded increase in the population since the 1970s. However, the most recent available data from incomplete non-pup surveys in 2006 and 2007 suggest that the overall trend for the western DPS, through 2007, is either stable or slightly declining. It is not known whether the changing trends in the western DPS are the result of management actions, natural changes in the ecosystem, or other factors. [Source: NMFS 2008]

The eastern DPS remains on an increasing trend (NMFS 2008). At least part of the increase reflects movement of individuals from the western DPS into the eastern DPS. For example, of the two most recently established rookeries in the eastern DPS, about 70 percent of the pups born on Graves Rock were from western DPS females, and about 45 percent of the pups born at White Sisters were from western DPS females (Gelatt et al. 2006, NMFS unpublished data, cited by NMFS 2008). Movement inferred from the genetics data has been confirmed by the sighting of western branded females with pups at Graves Rock and White Sisters (NMFS unpublished data, cited by NMFS 2008).

Long-term Trend: Decline of 70-90%
Long-term Trend Comments: The western distinct population segment (DPS) of Steller sea lions decreased from an estimated 220,000-265,000 animals in the late 1970s to fewer than 50,000 in 2000. The decline began in the 1970s in the eastern Aleutian Islands (Braham et al. 1980), western Bering Sea/Kamchatka and the Kuril Islands. In Alaska, the decline spread and intensified east and west of the eastern Aleutians in the 1980s and persisted at a slower rate through 2000 (Sease et al. 2001). The 12 percent increase in numbers of nonpups counted in the Alaskan range of the western DPS between 2000 and 2004 was the first region-wide increase observed during more than two decades of systematic surveys. The observed increase, however, has not been spread evenly among all regions of Alaska. Increases were noted in the eastern and western Gulf of Alaska and in the eastern and central Aleutian Islands, while the decline persisted through 2004 in the central Gulf of Alaska and the western Aleutian Islands. [Source: NMFS 2008]

The eastern DPS has increased at approximately 3 percent per year since the late 1970s (Pitcher et al. 2007).

Other NatureServe Conservation Status Information

Inventory Needs: Range-wide population minitoring should be continued (NMFS 2008).

Protection Needs: Current fishery conservation measures (or equivalent) should be maintained until substantive evidence demonstrates that these measures can be reduced without limiting recovery. (NMFS 2008).

Distribution
Help
Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Range includes coastal waters of the North Pacific Ocean from California and northern Honshu, Japan, and Korea, north to the Bering Strait (Kenyon and Rice 1961, Calkins and Pitcher 1983, Loughlin et al. 1984, Bigg 1988, Perlov 1991, Sea Lion Recovery Plan Team 1991, NMFS 2008). NMFS (2008) divides the population into eastern and western distinct population segments at 144° west longitude (Cape Suckling, Alaska).

Breeding rookeries extend from the central Kuril Islands and the Okhotsk Sea in the west to Aņo Nuevo Island and (formerly) San Miguel Island, California, in the east (Loughlin et al. 1987; NMFS 1993, 2008). Most of the largest rookeries formerly were in the Gulf of Alaska and the Aleutian Islands (Loughlin et al. 1984), but with the decline in the western distinct population segment the largest rookeries are now in Southeast Alaska and British Columbia (NMFS 2008). Breeding colonies occur in Oregon and British Columbia but not in Washington (nonbreeding occurrences only, mainly October to April).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AK, CA, OR, WA
Canada BC

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AK Aleutians East (02013), Aleutians West (CA) (02016), Bethel (CA) (02050), Dillingham (CA) (02070), Juneau (02110), Kenai Peninsula (02122), Ketchikan Gateway (02130), Kodiak Island (02150), Lake and Peninsula (02164), Nome (CA) (02180), Prince of Wales-Outer Ketchikan (CA) (02201), Sitka (02220), Skagway-Hoonah-Angoon (CA) (02232), Unorganized Borough (02999), Valdez-Cordova (CA) (02261), Wrangell-Petersburg (CA) (02280), Yakutat (02282)
CA Del Norte (06015), San Francisco (06075), San Mateo (06081)
OR Clatsop (41007), Coos (41011), Curry (41015), Lane (41039), Lincoln (41041), Tillamook (41057)
WA Clallam (53009)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
17 Lower Columbia (17080006)+, Hoh-Quillayute (17100101)+, Queets-Quinault (17100102)+, Necanicum (17100201)+, Wilson-Trusk-Nestuccu (17100203)+, Alsea (17100205)+, Coos (17100304)+, Sixes (17100306)+, Puget Sound (17110019)+
19 Southeast Mainland (19010101)+, Prince of Wales (19010103)+, Mainland (19010201)+, Kuiu-Kupreanof-Mitkof-Etolin-Zarembo-Wrangell Isla (19010202)+, Baranof-Chichagof Islands (19010203)+, Lynn Canal (19010301)+, Glacier Bay (19010302)+, Bering Glacier (19010402)+, Icy Strait-Chatham Strait (19010500)+, Lower Copper River (19020104)+, Eastern Prince William Sound (19020201)+, Western Prince William Sound (19020202)+, Prince William Sound (19020203)+, Kodiak-Afognak Islands (19020701)+, Shelikof Straight (19020702)+, Cold Bay (19030101)+, Fox Islands (19030102)+, Western Aleutian (19030103)+, Pribilof Islands (19030104)+, Togiak (19030305)+, Kuskokwim Delta (19030502)+, Nunavak-St. Matthew Islands (19030503)+, St. Lawrence Island (19050101)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Help
Basic Description: A large marine carnivore (sea lion).
General Description: Pelage, which lacks underfur, is tawny, yellowish brown, or reddish brown in adults (may appear to be darker when fur is wet), dark brown to blackish in pups; small external ears are present; all limbs are flipperlike, and the hind limbs can be turned forward and used in terrestrial locomotion. Adult males have long, coarse hair on the chest, shoulders, and back; the chest and neck are massive and muscular (Hall 1981, Nowak 1991). Newborn pups have a thick, dark-brown coat that molts to lighter brown after 6 months (Daniel 2003).

Steller sea lions are the largest otariid. Males grow larger than females. The average standard length is 282 cm in adult males and 228 cm in adult females (maximum of about 325 cm and 290 cm, respectively); weight of males averages 566 kg and females 263 kg (maximum of about 1,120 kg and 350 kg) (Fiscus 1961, Calkins and Pitcher 1982, Loughlin and Nelson 1986, Winship et al. 2001). Newborn pups are about 1 meter long and weigh 16-23 kg (Daniel 2003).

Diagnostic Characteristics: This species differs from the California sea lion in larger adult size (average male Stellar sea lion is about 282 cm and 566 kg; average male California sea lion is about 250 cm and 400 kg), paler pelage, absence of a protruding crest on the forehead of adult males, and presence of a large diastema between the fourth and fifth upper postcanine teeth.
Reproduction Comments: The life cycle includes several basic stages, minimally including recently born pups, dependent juveniles, independent juveniles, subadults, and adults.

Females give birth to single pups a few days after arriving at the rookery, late May to early July (mainly late June). Females mate with territorial males within 2 weeks of parturition; mating occurs June to mid-July. Implantation is delayed 3-4 months; total gestation period is about 1 year. Female stays with her pup for 3-13 days, then begins a series of 1-2-day feeding trips that extend over a period of several weeks, during which time the pup is left ashore. Young are weaned usually within 1 year in California; lactation usually lasts more than 1 year in Alaska. Females are sexually mature in 3-4 years (or up to 8 years); may breed into their early 20s (Mathisen et al. 1962, Pitcher and Calkins 1981); most adult females breed annually, though a high rate of reproductive failure results in a lower than 100 percent birth rate among adult females (estimated at 55-63 percent by Pitcher and Calkins 1981 and Calkins and Goodwin 1988). Males attain sexual maturity at 3-7 years old (Pitcher and Calkins 1981), but breeding (territorial) males typically are at least 7-8 years old (most often 9-13 years old in Alaska) (Thorsteinson and Lensink 1962, Loughlin et al. 1987, Raum-Suryan et al. 2002). Males may live up to around 20 years and females to around 30 years.

Ecology Comments: Predators include orcas (killer whales) and sharks.
Habitat Type: Marine
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: Steller sea lions are not known to make regular migrations, but they do move considerable distances (reviewed by NMFS 2008). For example, Raum-Suryan et al. (2002) analyzed resightings of 8,596 pups that were branded from 1975-1995 on rookeries in Alaska. Almost all resightings of young-of-the-year were within 500 km of the rookery where the pup was born, although subsequent observations documented movements of 11 month-old pups with their mothers of over 800 km. Juvenile animals were seen at much greater distances from their rookery of birth (up to 1,785 km). Sightings of adults were generally less than 500 km away from the natal rookery although adult males have since been seen over 1,000 km from the rookery where they held a territory (also their natal rookery). [Source: NMFS 2008]

Some individuals may move northward in the Bering Sea in fall and winter (Loughlin et al. 1987). In late summer and fall, individuals from northern breeding colonies migrate southward, while those (especially adult males) from southern breeding areas migrate northward.

Juveniles in the Gulf of Alaska tend to move away from their rookeries in the summer and cross the northern sections of the Gulf. In southeastern Alaska, the movement tends to occur as a shift from inside waters in winter to the outer coastal waters in the summer (Calkins and Pitcher 1982).

Females with dependent young feed relatively close to rookeries and haulouts because they must return at regular intervals to feed their offspring (NMFS 2008). In Alaska, females foraged within 50 km of rookeries in summer but ranged up to several hundred kilometers offshore in winter (Merrick and Loughlin 1997).

Dispersal of individuals from their natal rookeries may play a significant role in the metapopulation dynamics and recovery of this species. For example, new rookeries established recently in Southeast Alaska resulted at least in part from dispersal of individuals from the large Forrester Island rookery and from rookeries in the western distinct population segment (Calkins et al. 1999, Raum-Suryan et al. 2002, Pitcher et al. 2007; unpublished data from Alaska Department of Fish and Game and NMFS, cited by NMFS 2008).

Marine Habitat(s): Near shore, Pelagic
Estuarine Habitat(s): Tidal flat/shore
Terrestrial Habitat(s): Bare rock/talus/scree
Habitat Comments: Marine habitats include coastal waters near shore and over the continental slope; sometimes rivers are ascended in pursuit of prey. When not on land, the sea lions may congregate at nearshore traditional rafting sites, or move out to the edge of the continental shelf (Kajimura and Loughlin 1988, Sea Lion Recovery Plan Team 1991). While offshore, the sea lions are most often found within 35 km of shore (Kenyon and Rice 1961, Fiscus and Baines 1966, Fiscus et al. 1976, Bonnell et al. 1983) but may range out to several hundred kilometers offshore. The distance sea lions move offshore varies seasonally, with fewer animals being sighted at sea during the summer (Fiscus et al. 1976, Bonnell et al. 1983). Waters extending 0.9 km from rookeries (and major haulouts) were determined to be essential habitat by the Recovery Team (see NMFS 1993); these waters, plus an air zone extending 0.9 km above a rookery/major haulout and (in Alaska) a land zone extending 0.9 km landward from a rookery/major haulout are included in critical habitat designations.

The most commonly used terrestrial habitat types are rookeries and haulouts. Rookeries are areas where adults congregate for breeding and pupping. These habitats generally occur on beaches of remote islands with difficult access for humans and other mammalian predators (Sea Lion Recovery Plan Team 1991). The beaches can be sand, gravel, cobble, boulder, or bedrock. Female sea lions tend to select locations for pupping that are gently sloping and protected from waves (Sandegren 1970). Females often use the same pupping site in successive years and tend to breed in or near their natal colony (Calkins and Pitcher 1982). Rookery sites may be used as haulout sites during the nonbreeding season. Independent juveniles usually avoid rookeries (Gentry 1970, Sandegren 1970, Calkins and Pitcher 1983, Hoover 1988). From about two weeks after birth, the pups begin to spend increasing amounts of time in the intertidal areas and swimming near shore. Haulouts are areas used by adult sea lions during the nonbreeding season and by nonbreeding adults and subadults throughout the year (Sea Lion Recovery Plan Team 1991). Haulout locations include exposed rocks, reefs, beaches, jetties, breakwaters, navigational aids, floating docks, and sea ice. Selection of both rookery and haulout sites appears to depend on a number of factors including substrate type, degree of exposure to wind and waves, proximity to food resources, tradition of use, season, and the degree of human disturbance (Gentry 1970, Sandegren 1970, Calkins and Pitcher 1983, Hoover 1988, Johnson et al. 1989).

Adult Food Habits: Invertivore, Piscivore
Immature Food Habits: Invertivore, Piscivore
Food Comments: Steller sea lions feed opportunistically on fishes (mainly demersal and off-bottom schooling species) and cephalopods; sometimes also on various other invertebrates (cnidarians, sand dollars, worms, shelled mollusks, crustaceans, etc.) and rarely on birds or small pinnipeds (though males at St. George Island kill and eat large numbers of northern fur seal pups in late summer and fall).

Bulls fast for 1-2 months during during breeding season.

Throughout the year, feeding may occur in the vicinity of rookeries or far (hundreds of kilometers) away, and in shallow or deep water, depending on the sex and age of the individual and the season.

Adult Phenology: Circadian
Immature Phenology: Circadian
Phenology Comments: Activity occurs throughout the year. Most feeding apparently occurs at night, though diurnal feeding is also documented. Females with small young apparently feed mainly at night.
Colonial Breeder: Y
Length: 300 centimeters
Weight: 1000000 grams
Economic Attributes
Help
Economic Comments: Steller sea lion sometimes is viewed as a nuisance due to presumed economic impact on fisheries.

Historically this species was used for food, clothing, boat coverings, meat for fox farms, and craftwork. Current subsistence take (a couple hundred per year in Alaska in the early 2000s) for food, clothing, and craftwork is subject to federal management (in the United States) and is not regarded as contributing to population declines.

Management Summary
Help
Stewardship Overview: The recovery plan (NMFS 2008) identified 78 substantive actions needed to achieve recovery of the western DPS by addressing the broad range of threats. These actions address three main objectives: (1) the collection of information on status and vital rates, (2) research programs to collect information on the remaining threats to recovery, including natural and anthropogenic factors, and (3) the implementation of conservation measures to remove impacts of anthropogenic threats to recovery. The recovery plan highlighted four actions believed to be especially important to the recovery program for the western DPS: (1) continue population monitoring and research on the key threats potentially impeding sea lion recovery; (2) maintain current or equivalent level of fishery conservation measures; (3) design and implement an adaptive management program to evaluate fishery conservation; and (4) develop an implementation plan. See NMFS (2008) for further details.
Management Requirements: NMFS (2008) listed the following recent conservation actions that likely have benefited Steller sea lions: substantial reduction in disturbance of important rookeries and haulouts; substantial reduction in the incidental catch of Steller sea lions in commercial fishing operations, particularly the groundfish trawl fishery; significant efforts to reduce intentional take by prohibiting shooting at or near Steller sea lions; intensive research to better describe the threats to Steller sea lions and provide management with options for recovery actions; potential reduction in the competitive interactions between Steller sea lions and commercial fisheries for pollock, Atka mackerel, and Pacific cod in Alaska; acquired additional information on the status, foraging ecology, and survivorship of Steller sea lions.
Monitoring Requirements: See Westlake et al. (1997) for a comparison of vertical aerial photographic and ground censuses.
Management Research Needs: Research is needed on key threats potentially impeding sea lion recovery (NMFS 2008).

An adaptive management program to evaluate fishery conservation measures should be designed and implemented (NMFS 2008).

Population/Occurrence Delineation
Help
Use Class: Breeding
Subtype(s): Breeding rookery, Feeding Concentration Area
Minimum Criteria for an Occurrence: Evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes reliable observation and documentation of breeding individuals over several years. Breeding occurrences include both the terrestrial mating/pupping area and the surrounding waters used as feeding grounds.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Measured between terrestrial rookeries along shore or across straits. Distance arbitrary. During the breeding period, females travel up to about 30 kilometers from the rookery to feed; later in the summer, feeding trips are farther and last longer (Loughlin, in Wilson and Ruff 1999).
Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 30 km
Inferred Minimum Extent Justification: See Separation Justification.
Date: 09Aug2001
Author: Cannings, S.

Use Class: Nonbreeding
Subtype(s): Haulout site, Feeding Concentration Area
Minimum Criteria for an Occurrence: Evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes reliable observation and documentation of nonbreeding individuals over several years. Occurrences include both the terrestrial haulout area and the surrounding waters used as feeding grounds.
Mapping Guidance: Terrestrial haulout sites and associated feeding concentration areas should be mapped using separate polygons if separated by a commuting zone.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Measured between terrestrial haulouts along shore or across straits. Distance arbitrary. During the breeding period, females travel up to about 30 kilometers from the rookery to feed; later in the summer, feeding trips are farther and last longer (Loughlin, in Wilson and Ruff 1999).
Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 30 km
Inferred Minimum Extent Justification: See Separation Justification. Use this IE cautiously, since many marine environments may not be used for foraging.
Date: 04Feb2002
Author: Cannings, S.
Population/Occurrence Viability
Help
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Help
Authors/Contributors
Help
NatureServe Conservation Status Factors Edition Date: 25Jul2011
NatureServe Conservation Status Factors Author: Hammerson, G., and E. W. West
Element Ecology & Life History Edition Date: 15Jul2011
Element Ecology & Life History Author(s): Hammerson, G., and E. West

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
Help
  • Angell, T., and K. C. Balcomb, III. 1982. Marine birds and mammals of Puget Sound. Puget Sound Books, Washington Sea Grant Publication, distributed by University of Washington Press, Seattle.

  • B.C. Ministry of Environment. Recovery Planning in BC. B.C. Minist. Environ. Victoria, BC.

  • Banfield, A. W. F. 1974. The mammals of Canada. University of Toronto Press, Toronto, Canada. 438 pp.

  • Barlow, J., K.A. Forney, P.S. Hill, R.L. Brownell, J.V.Carretta, D.P. DeMaster, F. Julian, M.S. Lowry, T. Ragen, and R.R. Reeves. 1997. U.S. Pacific Marine Mammal Stock Assessments: 1996. NOAA Tech. Memo. NMFS. NOAA-TM-NMFS-SWFSC-248.

  • Bartholomew, G.A. and R.A. Boolootian. 1960. Numbers and population structure of the pinnipeds on the California Channel Islands. J. Mamm. 41(3):366-375.

  • Bickham, J. W., J. C. Patton, and T. R. Loughlin. 1996. High variability for control-region sequences in a marine mammal: implications for conservation and biogeography of Steller sea lions (EUMETOPIAS JUBATUS). Journal of Mammalogy 77:95-108.

  • Bickham, J. W., T. R. Loughlin, D. G. Calkins, J. K. Wickliffe, and J. C. Patton. 1998. Genetic variability and population decline in Steller sea lions from the Gulf of Alaska. Journal of Mammalogy 79:1390-1395.

  • Bigg, M. A. 1988. Status of the Steller sea lion, EUMETOPIAS JUBATUS, in Canada. Canadian Field-Naturalist 102:315-336.

  • Bigg, M.A. 1985. Status of the Steller Sea Lion (Eumetopias jubatus) and California Sea Lion (Zalophus californianus) in British Columbia. Can. Spec. Publ. Fish. and Aquatic Sci. No. 77.

  • Bigg, M.A. 1985. Status of the Steller sea lion (EUMETOPIAS JUBATUS) and California sea lion (ZALOPHUS CALIFORNIANUS) in British Columbia. Canad. Spec. Publ. Fish. Aquat. Sci. 77. 20 p.

  • Bigg, M.A. 1987. Status report on the Steller Sea Lion EUMETOPIAS JUBATUS in Canada. Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 46 pp.

  • Bigg, M.A. 1988. Status of the Steller sea lion, Eumetopias jubatus, in Canada. Can. Field-Nat. 102:315-336.

  • Bonnell, M.L., M.O. Pierson, and G.D. Farrens. 1983. Pinnipeds and sea otters of central and northern California, 1980-1983: status, abundance and distribution. Part of investigator's final report for contract #14-12-0001-29090. Prepared for U.S. Minerals Management Service. Center for Marine Studies, Univ. of California, Santa Cruz.

  • Bradley, R.D., L.K. Ammerman, R.J. Baker, L.C. Bradley, J.A. Cook. R.C. Dowler, C. Jones, D.J. Schmidly, F.B. Stangl Jr., R.A. Van den Bussche and B. Würsig. 2014. Revised checklist of North American mammals north of Mexico, 2014. Museum of Texas Tech University Occasional Papers 327:1-28. Available at: http://www.nsrl.ttu.edu/publications/opapers/ops/OP327.pdf

  • Braham, H.W., R.D. Everitt and D.J. Rugh. 1980. Northern sea lion population decline in the eastern Aleutian Islands. J. Wildl. Manage. 44(1):25-33.

  • Braham, H.W., R.D. Everitt and D.J. Rugh. 1980. Northern sea lion population decline in the eastern Aleutian Islands. J. Wildl. Manage. 44(1):25-33.

  • COSEWIC. 2003m. COSEWIC assessment and update status report on the Steller sea lion Eumetopias jubatus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 47 pp.

  • COSEWIC. 2013d. COSEWIC assessment and status report on the Steller Sea Lion Eumetopias jubatus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xi + 54 pp. 

  • Calkins, D. G., D. C. McAllister, K. W. Pitcher, and G. W. Pendleton. 1999. Steller sea lion status and trend in southeast Alaska: 1979-1997. Marine Mammal Science 15:462-477.

  • Calkins, D. G., and K. W. Pitcher. 1982. Population assessment, ecology and trophic relationships of Steller sea lions in the Gulf of Alaska. Pages 447-546 in Environmental assessment of the Alaskan continental shelf. U.S. Dept. Comm. And U.S. Dept. Int., Final Rep. Principal Investigators, 19:1-565.

  • Calkins, D. and E. Goodwin. 1988. Investigation of the declining sea lion population in the Gulf of Alaska. Unpubl. rep. Alaska Dept. Fish and Game, Anchorage, AK. 76 pp.

  • Calkins, D. and E. Goodwin. 1988. Investigation of the declining sea lion population in the Gulf of Alaska. Unpubl. rep. Alaska Dept. Fish and Game, Anchorage, AK. 76 pp.

  • Calkins, D., and K. Pitcher. 1983. 1982 pinniped investigations in southern Alaska. Unpubl. rep. Alaska Dept. of Fish and Game, Anchorage, AK. 11 p. + tables.

  • Calkins, D., and K. Pitcher. 1983. 1982 pinniped investigations in southern Alaska. Unpubl. rep. Alaska Dept. of Fish and Game, Anchorage, AK. 11 p. + tables.

  • Calkins, D.G. and K.W Pitcher. 1982. Population assessment, ecology, and trophic relationships of Steller sea lions in the Gulf of Alaska. Final report for Outer Continental Shelf Environmental Assessment Program. Alaska Dept. Fish and Game, Anchorage, AK.Bureau of Land Mangement. 129 p.

  • Committee on the Alaska Groundfish Fishery and Steller Sea Lions. 2003. Decline of the Steller sea lion in Alaskan waters. National Academies Press, Washington, D.C.

  • Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 1999. Canadian Species at Risk: April 1999. Committee on the Status of Endangered Wildlife in Canada, Ottawa, Ontario, Canada. 17 pp.

  • Daniel, R. G. 2003. The timing of moulting in wild and captive Steller sea lions (Eumetopias jubatus). M.Sc. thesis, University of British Columbia, Vancouver, British Columbia, Canada. 64 pp.

  • DeLong, R.L., W.G. Gilmartin, and J.G. Simpson. 1973. Premature births in California sea lions: association with high organochlorine pollutant residue levels. Science 181:1168-1170.

  • Edie, A.G. 1977. Distribution and movements of Steller sea lion cows (Eumetopias jubatus) on a pupping colony. M.Sc. Thesis, Univ. B.C., Vancouver, BC.

  • Eumetopias jubatus/Steller Sea Lion. Copyright Dave Fraser.

  • Fiscus, C. H. 1961. Growth in the Steller sea lion. Journal of Mammalogy 42:195-200.

  • Fiscus, C.H. and G.A. Baines. 1966. Food and feeding behavior of Steller and California sea lions. J. Mamm. 47(2):195-200.

  • Fiscus, C.H. and G.A. Baines. 1966. Food and feeding behavior of Steller and California sea lions. J. Mamm. 47(2):195-200.

  • Fiscus, C.H., H.W. Braham, R.W. Mercer, R.D. Everitt, B.D. Krogman, P.D. McGuire, C.E. Peterson, R.M. Sonntag and D.E. Withrow. 1976. Seasonal distribution and relative abundance of marine mammals in the Gulf of Alaska. Pp. 19-264. In: Environmental assessment of the Alaskan continental shelf. Vol.1. Principal investigators' reports, October-December 1976. U.S. Dept. Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Boulder, CO.

  • Fisheries and Oceans Canada. 2010. Management Plan for the Steller Sea Lion (Eumetopias jubatus) in Canada [Proposed]. Species at Risk Act Management Plan Series. Fisheries and Oceans Canada, Ottawa. vi + 69 pp.

  • Fisheries and Oceans Canada. 2010d. Management Plan for the Steller Sea Lion (Eumetopias
    jubatus) in Canada [Final]. Species at Risk Act Management Plan Series. Fisheries and Oceans
    Canada, Ottawa. vi + 69 pp.

  • Fraker, B.A., and B.R. Mate. 1999. Seals, sea lions, and salmon in the Pacific Northwest. Pages xx in J.R. Twiss, and R.R. Reeves, eds. Marine Mammals, vol. 2, Management. Smithsonian Press, Washington, DC. In press.

  • Gelatt, T. S., A. W. Trites, K. Hastings, L. Jemison, K. Pitcher, and G. O'Corry-Crowe. 2006. Population trends, diet, genetics, and observations of Steller sea lions in Glacier Bay National Park. Pages 145-149 in J.F. Piatt and S.M. Gende, editors. Proceedings of the Fourth Glacier Bay Science Symposium, October 26-28, 2004. U.S. Geological Survey Scientific Investigations Report 2007-5047.

  • Gentry, R.L. 1970. Social behavior of the Steller sea lion. Ph.D. thesis. Univ. of California, Santa Cruz, CA. 113 p.

  • Gentry, R.L. 1970. Social behavior of the Steller sea lion. Ph.D. thesis. Univ. of California, Santa Cruz, CA. 113 p.

  • Gilmartin, W.G., R.L. DeLong, A.W. Smith, J.C. Sweeney, B.W. DeLappe, R.W. Risebrough, L.A. Griner, M.D. Dailey, and D.B. Peakall. 1976. Premature parturition in the California sea lion. J.Wildl. Diseases 12:104-115.

  • Hall, E. R. 1981a. The Mammals of North America, second edition. Vols. I & II. John Wiley & Sons, New York, New York. 1181 pp.

  • Hall, E. R. 1981a. The Mammals of North America, second edition. Vols. I & II. John Wiley & Sons, New York, New York. 1181 pp.

  • Harlin-Cognato, A., J. W. Bickham, T. R. Loughlin, and R. L. Honeycutt. 2006. Glacial refugia and the phylogeography of Steller's sea lion (Eumatopias jubatus) in the North Pacific. Journal of Evolutionary Biology 19:955-969.

  • Harrison, R.J. 1969. Reproduction and reproductive organs. Pages 253-384 in H.T. Anderson, ed. The biology of marine mammals. Acad. Press, New York, NY.

  • Harwood, J., and J.P. Croxall. 1988. The assessment of competition between seals and commercial fisheries in the North Sea and the Antarctic. Marine Mammal Sci. 4:13-33.

  • Holmes, E. E., and A. E. York. 2003. Using age structure to detect impacts on threatened populations: a case study with Steller sea lions. Conservation Biology 17:1794-1806.

  • Honacki, J. H., K. E. Kinman, and J. W. Koepf (eds.). 1982. Mammal species of the world. Allen Press, Inc. and Assoc. Syst. Coll., Lawrence, Kansas. 694 pp.

  • Hoover, A.A. 1988. Steller sea lion, EUMETOPIAS JUBATUS. Pp. 159-193. In: Lentfer, J.W. (ed.). Selected marine mammals of Alaska: species accounts with research and management recommendations. Marine Mammal Commission, Washington, DC.

  • Hoover, A.A. 1988. Steller sea lion, EUMETOPIAS JUBATUS. Pp. 159-193. In: Lentfer, J.W. (ed.). Selected marine mammals of Alaska: species accounts with research and management recommendations. Marine Mammal Commission, Washington, DC.

  • Ingles, L. G. 1965. Mammals of the Pacific States. Stanford University Press, Stanford, California.

  • Johnson, S.R., J.J. Burns, C.I. Malme, and R.A. Davis. 1989. Synthesis of information on the effects of noise and disturbance on major haulout concentrations of Bering Sea pinnipeds. Report by LGL for Minerals Management Service, Anchorage, AK. 267 p.

  • Jones, J. K., Jr., R. S. Hoffman, D. W. Rice, C. Jones, R. J. Baker, and M. D. Engstrom. 1992a. Revised checklist of North American mammals north of Mexico, 1991. Occasional Papers, The Museum, Texas Tech University, 146:1-23.

  • Kajimura, H. and T.R. Loughlin. 1988. Marine mammals in the oceanic food web of the eastern subarctic Pacific. Bull. Ocean. Res. Inst. 26:187-223.

  • Kenyon, K.W. 1962. History of the Steller sea lion at the Pribilof islands, Alaska. J. Mammal. 43:68-75.

  • Kenyon, K.W. and D.W. Rice. 1961. Abundance and distribution of the Steller sea lion. J. Mamm. 42(2):223-234.

  • Kenyon, K.W. and D.W. Rice. 1961. Abundance and distribution of the Steller sea lion. J. Mamm. 42(2):223-234.

  • King, J. E. 1983. Seals of the world. Second edition. Cornell Univ. Press, Ithaca.

  • Loughlin, T. R., A. S. Perlov, and A. A. Vladimirov. 1992. Range-wide survey and estimation of total number of Steller sea lions in 1989. Marine Mammal Science 8:220-239.

  • Loughlin, T. R., D. J. Rugh, and C. H. Fiscus. 1984. Northern sea lion distribution and abundance: 1956-1980. J. Wildlife Management 48:729-740.

  • Loughlin, T. R., M. A. Perez, and R. L. Merrick. 1987. Eumetopias jubatus. Am. Soc. Mamm., Mammalian Species No. 283:1-7.

  • Loughlin, T. R., and R. Nelson, Jr. 1986. Incidental mortality of northern sea lions in Shelikof Strait, Alaska. Marine Mammal Science 2:14-33.

  • Loughlin, T.R. 1997. Using the phylogeographic method to identify Steller sea lion stocks. Pages 159-171 in A.E. Dizon, S.J. Chivers, and W.F. Perrin, eds. Molecular genetics of marine mammals. The Soc. for Marine Mammal. Spec. Publ. No. 3.

  • Loughlin, T.R., A.S. Perlov and V.A. Vladimirov. 1990. Survey of northern sea lions (EUMETOPIAS JUBATUS) in the Gulf of Alaska and Aleutian Islands during June 1989. U.S. Dept. Commerce, National Marine Fisheries Service, Alaska Fisheries Science Center, National Marine Mammal Laboratory, Seattle, WA. 26 p.

  • Loughlin, T.R., A.S. Perlov and V.A. Vladimirov. 1990. Survey of northern sea lions (EUMETOPIAS JUBATUS) in the Gulf of Alaska and Aleutian Islands during June 1989. U.S. Dept. Commerce, National Marine Fisheries Service, Alaska Fisheries Science Center, National Marine Mammal Laboratory, Seattle, WA. 26 p.

  • Loughlin, T.R., D.J. Rugh and C.H. Fiscus. 1984. Northern sea lion distribution and abundance: 1956-1980. J. Wildl. Manage. 48(3):729-740.

  • Loughlin, T.R., and R.L. Merrick. 1989. Comparison of commercial harvest of walleye pollock and the northern sea lion abundance in the Bering Sea and the Gulf of Alaska. Pages 679-700, in Proc. Inter. symp. on the biol. and manage. of walleye pollock, 14-16 November 1988, Anchorage, AK. Univ. Alaska Sea Grant Rep. AK-SG-89-01.

  • Lowry, L.F., K.J. Frost, D.G. Calkins, G.L. Swartzman, and S. Hills. 1982. Feeding habits, food requirements, and status of Bering Sea marine mammals. North Pacific Fishery Manage. Council, Anchorage, AK. Document No. 19.

  • Maser, C., B. R. Mate, J. F. Franklin, and C. T. Dyrness. 1981. Natural history of Oregon coast mammals. Pacific Northwest Forest and Range Expt. Sta., USDA, Forest Service, Gen Tech. Rep. PNW-133:1-496.

  • Mathisen, O.A., R.T. Baade, and R.J. Lopp. 1962. Breeding habits, growth and stomach contents of the Steller sea lion in Alaska. J. Mammal. 43:464-477.

  • Mathisen, O.A., R.T. Baade, and R.J. Lopp. 1962. Breeding habits, growth and stomach contents of the Steller sea lion in Alaska. J. Mammal. 43:464-477.

  • Mello, S. 1994. Status of the Steller sea lion, EUMETOPIAS JUBATUS, in Alaska. Endangered Species Update 11(12):1-6.

  • Merrick, R. L., D. G. Calkins, and D. C. McAllister. 1992. Aerial and ship-based surveys of Steller sea lions (EUMETOPIAS JUBATUS) in the Gulf of Alaska and Aleutian Islands during June and July 1991. U.S. Dept. Commerce NOAA Tech. Memo. NMFS-AFSC-1.

  • Merrick, R. L., and T. R. Loughlin. 1997. Foraging behavior of adult female and young-of-the-year Steller sea lions in Alaskan waters. Canadian Journal of Zoology 75:776-786.

  • Merrick, R.L., L.M. Ferm, R.D. Everitt, R.R. Ream and L.A. Lessard. 1991. Aerial and ship-based surveys of northern sea lions (EUMETOPIAS JUBATUS) in the Gulf of Alaska and Aleutian Islands during June and July 1990. Tech. Memo. F/NWC-196. U.S. Dept. Commerce, Nat. Oceanic and Atmospheric Admin., Nat. Marine Fisheries Service, Nat. Marine Mammals Lab., Seattle, WA. 34 p.

  • Merrick, R.L., L.M. Ferm, R.D. Everitt, R.R. Ream and L.A. Lessard. 1991. Aerial and ship-based surveys of northern sea lions (EUMETOPIAS JUBATUS) in the Gulf of Alaska and Aleutian Islands during June and July 1990. Tech. Memo. F/NWC-196. U.S. Dept. Commerce, Nat. Oceanic and Atmospheric Admin., Nat. Marine Fisheries Service, Nat. Marine Mammals Lab., Seattle, WA. 34 p.

  • Merrick, R.L., M.K. Maminov, J.D. Baker and A.G. Makhnyr. 1990. Results of U.S.-U.S.S.R. joint marine mammal research cruise in the Kuril and Aleutian Islands 6 June-24 July 1989. NOAA Technical Memorandum NMFS F/NWC-177. U.S. Dept. Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, National Marine Mammal Laboratory, Seattle, WA. 63 p.

  • Merrick, R.L., T.R. Loughlin and D.G. Calkins. 1987. Decline in abundance of the northern sea lion, EUMETOPIAS JUBATUS, in Alaska, 1956-86. Fish. Bull. 85(2):351-365.

  • Merrick, R.L., T.R. Loughlin and D.G. Calkins. 1987. Decline in abundance of the northern sea lion, EUMETOPIAS JUBATUS, in Alaska, 1956-86. Fish. Bull. 85(2):351-365.

  • National Marine Fisheries Service (NMFS). 13 December 2010. 90-day finding on petitions to delist the eastern distinct population segment of the Steller sea lion. Federal Register 75(238):77602-77605.

  • National Marine Fisheries Service (NMFS). 1990. Listing of Steller sea lions as threatened under endangered species act with protective regulations. Emergency interim rule and request for comments. April 5, 1990. Federal Register 55(66):12645-12662.

  • National Marine Fisheries Service (NMFS). 1990. Listing of Steller sea lions as threatened under the Endangered Species Act. Final rule. Nov. 26, 1990. Federal Register 55(227):49204-49241.

  • National Marine Fisheries Service (NMFS). 2008. Recovery plan for the Steller sea lion eastern and western distinct population segments (Eumetopias jubatus). Revision. National Marine Fisheries Service, Silver Spring, MD. 325 pages.

  • National Marine Fisheries Service. 1990. Listing of Steller sea lions as threatened under the Endangered Species Act. Final rule. Nov. 26, 1990. Federal Register 55(227):49204-49241.

  • National Marine Fisheries Service. 1992. Recovery Plan for the Steller Sea Lion (Eumetopias jubatus). Natl. Marine Fish. Serv., Silver Spring, MD. 92pp.

  • Nowak, R. M. 1991. Walker's mammals of the world. Fifth edition. Vols. I and II. Johns Hopkins Univ. Press, Baltimore. 1629 pp.

  • Olesiuk, P.F. 2011. Abundance of Steller sea lions (Eumetopias jubatus) in British Columbia. Canadian Science Advisory Secretariat Research Document 2010/000:1-43. (as cited in COSEWIC 2013; original unavailable).

  • Olesiuk, P.F., M.A. Bigg, G.M. Ellis, S.J. Crockford, and R.J. Wigen. 1990. An assessment on the feeding habits of harbour seals (Phoca vitulina) in the Strait of Georgia, British Columbia, based on scat analysis. Can. Tech. Rep. Fish. Aquat. Sci. No. 1730.

  • Parks Canada. 2000. Vertebrate Species Database. Ecosystems Branch, 25 Eddy St., Hull, PQ, K1A 0M5.

  • Pascual, M. A., and M. D. Adkison. 1994. The decline of the Steller sea lion in the northeast Pacific: demography, harvest or environment? Ecological Applications 4:393-403.

  • Perlov, A.S. 1971. The onset of sexual maturity in sea lions. Proc. All Union Inst. Mar. Fish. and Oceanography 80:174-187.

  • Perlov, A.S. 1991. Present abundance of Steller sea lions (Eumetopias jubatus) in the U.S.S.R. AFSC Processed Report 91-14. U.S. Dept. Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, Seattle, WA.

  • Pike, G.C., and B.E. Maxwell. 1958. The abundance and distribution of the northern sea lion (Eumetopias jubatus) on the coast of British Columbia. J. Fish. Res. Board of Can. 13:5-17.

  • Pitcher, K. W., D. G. Calkins, and G. W. Pendleton. 1998. Reproductive performance of female Steller sea lions: an energetics-based reproductive strategy? Canadian Journal of Zoology 76:2075-2083.

  • Pitcher, K. W., P. F. Olesiuk, R. F. Brown, M. S. Lowry, S. J. Jeffries, J. L. Sease, W. L. Perryman, C. E. Stinchcomb, and L. F. Lowry. 2007. Abundance and distribution of the eastern North Pacific Steller sea lion (Eumetopias jubatus) population. Fishery Bulletin 107:102-115.

  • Pitcher, K. W., and D. G. Calkins. 1981. Reproductive biology of Steller sea lions in the Gulf of Alaska. Journal of Mammalogy 62:599-605.

  • Pitcher, K.W. 1981. Prey of Steller sea lion, Eumetopias jubatus, in the Gulf of Alaska. Fish. Bull. 79:467-472.

  • Pitcher, K.W., and D.G. Calkins. 1981. Reproductive biology of the Steller sea lion in the Gulf of Alaska. J. Mammal. 62:599-605.

  • Raum-Suryan, K. L., K. W. Pitcher, D. G. Calkins, J. L. Sease, and T. R. Loughlin. 2002. Dispersal, rookery fidelity and metapopulation structure of Steller sea lions (Eumetopias jubatus) in an increasing and a decreasing population in Alaska. Marine Mammal Science 18:746-764.

  • Reeves, R. R., B. S. Stewart, and S. Leatherwood. 1992. The Sierra Club Handbook of Seals and Sirenians. Sierra Club Books, San Francisco, California. xvi + 359 pp.

  • Riedman, M. 1990a. The Pinnipeds: Seals, Sea Lions and Walruses. University of California Press, Berkeley, California. xxiii + 439 pp.

  • Sandegren, F.E. 1970. Breeding and maternal behavior of the Steller sea lion (EUMETOPIAS JUBATA) in Alaska. M.S. thesis. Univ. of Alaska Fairbanks, Fairbanks, AK. 138 p.

  • Sandegren, F.E. 1970. Breeding and maternal behavior of the Steller sea lion (EUMETOPIAS JUBATA) in Alaska. M.S. thesis. Univ. of Alaska Fairbanks, Fairbanks, AK. 138 p.

  • Scheffer,Victor B. 1958. Seals, Sea lions and Walruses: A review of the Pinnipedia. Stanford University Press, Stanford,CA.

  • Schusterman, R. J. 1981. Steller sea lion Eumetopias jubatus (Schreber, 1776). Pages 119-141 in S. H. Ridgway and R. J. Harrison, editors. Handbook of marine mammals. Vol. 1. The walrus, sea lions, fur seals and sea otter. Academic Press, New York.

  • Sea Lion Recovery Plan Team. 1991. Recovery plan for the Steller sea lion (EUMETOPIAS JUBATUS), final revision. Multi-agency cooperative report. October 3, 1991. 119 p.

  • Sea Lion Recovery Plan Team. 1991. Recovery plan for the Steller sea lion (EUMETOPIAS JUBATUS), final revision. Multi-agency cooperative report. October 3, 1991. 119 p.

  • Sease, J. L., W. P. Taylor, T. R. Loughlin, and K. W. Pitcher. 2001. Aerial and land-based surveys of Steller sea lions (Eumetopias jubatus) in Alaska, June and July 1999 and 2000. NOAA Tech. Memo. NMFS-AFSC-122. 52 pp.

  • Spalding, D.J. 1964. Comparative feeding habits of the fur seal, sea lion and the harbour seal on the British Columbia coast. Bull. Fish. Res. Board Can. 146:1-52.

  • The Marine Mammal Centre (TMMC). 2000. Stellar Sea Lion (SSL) or Northern Sea Lion. Available online at: www.marinemammalcenter.org/learning/education/pinnipeds/stellarsea.asp.

  • Thorsteinson, F. V., and C. J. Lensink. 1962. Biological observations of Steller sea lions taken during an experimental harvest. Journal of Wildlife Management 26:353-359.

  • Trujillo, R. G., T. R. Loughlin, N. J. Gemmell, J. C. Patton, and J. W. Bickham. 2004. Variation in microsatellites and mtDNA across the range of the Steller sea lion, Eumetopias jubatus. Journal of Mammalogy 85:338-346.

  • U.S. Fish and Wildlife Service (USFWS). 1993. Designated critical habitat; Steller sea lion. Federal Register 58(165):45269-45285. 27 August 1993.

  • U.S. Fish and Wildlife Service. 1990. Listing of Steller sea lions as threatened under the endangered species act. November 26, 1990. Federal Register 55(227):49204-49241.

  • Washington Department of Wildlife. 1993. Status of the Stellar (northern) Sea Lion (Eumotopias jubatus) in Washington. Unpublished Report Washington Department of Wildlife, Olympia.

  • Westlake, R. L., W. L. Perryman, and K. A. Ono. 1997. Comparison of vertical aerial photographic and ground censuses of Steller sea lions at Ano Nuevo Island, July 1990-1993. Marine Mammal Science 13:207-218.

  • Wiles, G.J. 2015. Washington state periodic status review for the Steller sea lion. Washington Department of Fish and Wildlife, Olympia, Washington. 38 pp.

  • Wilson, D. E., and D. M. Reeder (editors). 1993. Mammal species of the world: a taxonomic and geographic reference. Second edition. Smithsonian Institution Press, Washington, DC. xviii + 1206 pp. Available online at: http://www.nmnh.si.edu/msw/.

  • Wilson, D. E., and S. Ruff. 1999. The Smithsonian book of North American mammals. Smithsonian Institution Press, Washington, D.C. 750 pp.

  • Winship, A. J., A. W. Trites and D. G. Calkins. 2001. Growth in body size of Steller sea lions (Eumetopias jubatus). Journal of Mammalogy 82:500-519.

  • York, A.E. 1994. The population dynamics of northern sea lions, 1975-1985. Marine Mammal Sci. 10:38-51.

Use Guidelines & Citation

Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at http://explorer.natureserve.org were updated to be current with NatureServe's central databases as of March 2019.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2019 NatureServe, 2511 Richmond (Jefferson Davis) Highway, Suite 930, Arlington, VA 22202, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2019. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.