Species: Eschrichtius robustus

Gray Whale
Species
    Grey whale breaching

    This is a large, gray mottled baleen whale lacking a dorsal fin. The head is narrow with an arched profile. Baleen is yellowish white and 2-10 inches (5-25 cm) long. Two nostrils are present. A middorsal hump is followed by a series of about 6-12 bumps. Flippers are short and broad. Body is varyingly colored by patches of barnacles and cyamid crustaceans. Calves are more uniformly dark than are adults. Maximum length is around 50 feet (15 meters). Sources: Leatherwood and Reeves (1983), Nowak (1991).

    Articles:

    Biomarkers update insights on reproductive physiology of gray whales

    An article published in PLoS ONE in 2021 describes a study of hormone concentrations in gray whales. The findings may contribute to increased knowledge of reproductive physiology and population dynamics among the species.

    Gray whale and calf
    "Sounders" arrive as gray whales decline along the coast

    Each spring, about a dozen gray whales make a brief detour into the Salish Sea before heading north to their feeding grounds in the Arctic. Biologists dubbed these whales "Sounders" after first noting their presence in the 1990s, and the whales have become rare but widely anticipated visitors to local waters. The whales were spotted again this year, but biologists have documented a 24 percent decline in gray whale populations along the West Coast.

    Tail of a gray whale showing above water
    Gray Whale (Eschrichtius robustus)

    This article was originally published by the Washington Department of Fish and Wildlife as part of its annual report Threatened and Endangered Wildlife in Washington.

    Gray whale (photo by Chris Johnson).
    Kingdom
    Animalia
    Phylum
    Craniata
    Class

    Mammalia

    Order

    Cetacea

    Family

    Eschrichtiidae

    Genus

    Eschrichtius

    Classification
    Other Global Common Names
    Grey Whale - baleine grise
    Informal Taxonomy
    <p>Animals, Vertebrates - Mammals - Whales and Dolphins</p>
    Formal Taxonomy
    Animalia - Craniata - Mammalia - Cetacea - Eschrichtiidae - Eschrichtius - .

    This is a large, gray mottled baleen whale lacking a dorsal fin. The head is narrow with an arched profile. Baleen is yellowish white and 2-10 inches (5-25 cm) long. Two nostrils are present. A middorsal hump is followed by a series of about 6-12 bumps. Flippers are short and broad. Body is varyingly colored by patches of barnacles and cyamid crustaceans. Calves are more uniformly dark than are adults. Maximum length is around 50 feet (15 meters). Sources: Leatherwood and Reeves (1983), Nowak (1991).

    Short General Description
    A large baleen whale.
    Habitat Type Description
    Marine
    Migration
    <p>false - false - true - The western Pacific stock migrates south from western and northern Sea of Okhotsk to the southern coast of China (Rice, in Wilson and Ruff 1999).</p>
    Non-migrant
    false
    Locally Migrant
    false
    Food Comments
    In the southern Chukchi Sea and northern Bering Sea, gray whales eat mainly tube-dwelling gammaridean amphipods; also various other small bottom invertebrates in small quantity. In the southern Bering Sea along the eastern Alaska Peninsula and adjacent Alaskan mainland, shrimp and mysids are the major prey. In Puget Sound, the whales feed on epibenthic ghost shrimp in littoral sand flats (Weitkamp et al. 1992). Elsewhere feeding is less common and prey may include swarms of amphipods, cumaceans, mysids, and infaunal polychaetes. <br><br>Gray whales employ a feeding technique not used by other large whales. While swimming forward and rolling to one side they run the head along the bottom and filter small invertebrates from the mud-water interface. They also may ingest invertebrates associated with masses of algae that are scraped through the mouth.
    Reproduction Comments
    Females are impregnated during the southward migration or close to calving grounds. Gestation lasts about 13.5 months. A single calf is born late December-early February. Weaning occurs within 9 months. The calving interval is usually 2 years. Individuals become sexually mature in 5-11 years.
    Ecology Comments
    In the northern Bering Sea, various seabirds (northern fulmar, red phalarope, black-legged kittiwake, and thick-billed murre) commonly forage on prey in the mud plumes stirred up by feeding gray whales.
    Length
    1410
    Weight
    3.3E7
    NatureServe Global Status Rank
    G4
    Global Status Last Reviewed
    2002-08-15
    Global Status Last Changed
    2002-08-15
    Conservation Status Map
    <img src="http://www.natureserve.org/explorer/servlet/GetMapGif?CA.BC=S3&US.AK=S4&US.CA=SNR&US.HI=SNR&US.NC=SX&US.OR=__&US.WA=__" alt="Conservation Status Map" style="width: 475px; height: auto;" />
    Global Range
    FG - 20,000-2,500,000 square km (about 8000-1,000,000 square miles) - FG - Range includes coastal waters of the North Pacific. Most gray whales are in the Bering and Chukchi seas in summer (some occur then off northern Alaska, the Siberian coast, and southward along the coast to British Columbia and northern California). In winter, they occur in coastal waters off Baja California, Sonora, and Sinaloa. Primary birthing areas are Laguna Ojo de Liebre (Scammon's Lagoon), Laguna Guerrero Negro, Laguna San Ignacio, and Estero Soledad, Mexico (IUCN 1991). This species has been extirpated in the Atlantic (last seen about 1750; Rice 1998, Nowak 1991). A small population exists in the western Pacific (Okhotsk Sea in summer to South Korean coast in winter) (Weller et al. 1999).
    Global Range Code
    FG
    Global Range Description
    20,000-2,500,000 square km (about 8000-1,000,000 square miles)
    ELEMENT_GLOBAL.2.104316