Histriophoca fasciata

"Ribbon seals are rarely seen on land. In late winter and spring they are on pack ice, 100-200 km offshore, where they molt, mate, and pup. They are probably far out in northern seas the rest of the year, feeding on fish such as pollock, cod, eelpout, and capelin, supplemented with squid, octopus, and shrimp. Ribbon seals have a large inflatable air sac that is connected to the windpipe and extends on the right side over the ribs. Larger in males, it may be to produce underwater vocalizations, perhaps for mating communication. Biologists believe these and many other seals have extensive social interactions underwater. Their ""ribbons"" are white or yellowish bands on the neck, flippers, and body that contrast with their otherwise dark fur."

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Mammal Species of the World

Ribbon Seal: Banded ice seal of the North Pacific

Light gray bands on dark background, most prominent in adult males; Bands across neck, front flippers, and torso

Ribbon seals inhabit the Bering, Chukchi, and Okhotsk seas and high latitudes of the western and central North Pacific Ocean (Stewart 1983), from Hokkaido and the northern Sea of Japan (Mizuno et al. 2002) north and offshore to the East Siberian Sea in the Russian Federation to the western Beaufort Sea (Moore and Barrowclough 1984) and south to the Alaska Peninsula in the United States (Angliss and Outlaw 2005). A sub-adult was killed near Cordova Alaska (Burns 1981), a debilitated vagrant was found beached in Morro Bay California (Roest 1964) and an adult has been observed in the Tsushima Strait (Heptner 1996).

Ribbon seals are found in coastal areas of the north Pacific Ocean and in the seas bordering Alaska and Russia. The largest populations are in the Bering or Okhotsk seas.

Biogeographic Regions: arctic ocean (Native ); pacific ocean (Native )

occurs (regularly, as a native taxon) in multiple nations

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Mainly pack ice from Hokkaido and the Sea of Okhotsk to northern Alaska and the Aleutian Islands; from late winter to early summer concentrated in ice-covered parts of the Chukchi, Bering, and Okhotsk seas and adjacent straits and bays (Nowak 1991). Most common in the Bering and Okhotsk seas; apparently relatively few summer in the Chukchi Sea (Reeves et al. 1992). Okhotsk Sea population may move into the Bering Sea for the summer.

The common name "ribbon seals" reflects the markings of their coat. The adult coat of a ribbon seal is most easily described as a dark background with four light colored stripes running in a circle around the animal. One stripe encircles the neck, another encircles the mid-posterior portion of the seal's body, and the other two stripes start ventrally and encircle the fore flippers on either side. Although this is the general pattern for all ribbon seals, there can be great individual variability as to the shade and precise location of the stripes. Males tend to be darker than females. Newborn and juvenile ribbon seals do not have this striped pattern; as newborns are completely white, while juvenile seals are dark anteriorally and dorsally, and grayish posteriorly and ventrally. Other ribbon seal traits include large eyes and small teeth. An adult will grow to about 1.6 m and weigh 70 kg, and has a lifespan of about 20 years.

Range mass: 70 to 80 kg.

Range length: 1.6 (high) m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike

Length: 150 cm

Weight: 90000 grams

Length:
Range: 1.6-1.7 m

Weight:
Range: 70-80 kg

Differs from other northern phocids by the unique color pattern and in having a relatively longer and more flexible neck, a shorter rostrum, and more widely spaced teeth (Nowak 1991).

Habitat and Ecology

Systems

• Terrestrial
• Marine

Ribbon seals are restricted to the cold waters of the northern Pacific. In winter and spring they forage and raise offspring on coastal ice flows, the summer months are spent in the open ocean.

Habitat Regions: temperate ; polar ; saltwater or marine

Terrestrial Biomes: icecap

Aquatic Biomes: pelagic ; coastal

Habitat Type: Marine

Comments: Associated with sea ice during late winter, spring, and early summer; prefers to haul out on moderately thick, clean ice, generally on ice floes well out to sea (Nowak 1991). Rarely hauls out on shore-fast ice and almost never on land. Gives birth on moderately thick, clean sea ice (Nowak 1991), generally far offshore (except when ice edge is near St. Matthew and St. Lawrence islands).

Northern North Pacific Ocean, Bering and Chukchi Seas, Sea of Okhotsk; Associated with sea ice during spring and in open water other seasons

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

At least some migrate northward and southward with the receding and advancing ice edge.

Ribbon seals eat primarily fish, taking fish species depending on their relative abundance in the area. Ribbon seals also eat squid, shrimp, and crabs. Juvenile seals have been reported to eat a lare proportion of crustaceans.

Animal Foods: fish; mollusks; aquatic crustaceans

Primary Diet: carnivore (Piscivore )

Comments: Feeds opportunistically on crustaceans, fishes (important species include walleye pollock and arctic cod), and cephalopods. Food intake is reduced during spring molt.

Both pelagic and demersal fishes (walleye pollock, capelin, arctic cod, and others) and cephalopods

Usually solitary, though scattered individuals may assemble on favorable ice flows (Nowak 1991). Mortality during the first four years of life is nearly 58% (Reeves et al. 1992).

Communication Channels: acoustic

Perception Channels: visual ; acoustic

Size at birth 0.9m (3 ft), 9-10kg (20-25 lbs); Sexual maturity at 3-5 years; Females have pups every year; Longevity 25-30 years; Behavior; Move by 'running' rather than 'caterpillaring' across ice; Haul out on ice in pairs or small groups

Ribbon seals live about 20 years in the wild.

Typical lifespan
Status: wild: 20 (high) years.

Observations: In the wild, these animals have been estimated to live up to 31 years (David Macdonald 1985), which has not been confirmed. Their longevity in captivity has not been studied in detail.

Males have a well-developed air sac extending from the posterior trachea. The function is unknown but it is likely to be used in underwater vocalizations that may be to attract females and compete for mates.

Mating System: polygynous

Adult females become pregnant once a year, giving birth sometime in April or May. Typically ribbon seals give birth to one pup with the birthing occurring on ice flows. Nursing lasts up to a month, a time during which the weight of the pup will double. As soon as the pups are weaned, adults will mate again. Ribbon seals employ a delayed implantation of two or three months, this is most likely to assure the presence of ice at the time of birth. After weaning, pups spend a lot of time practicing diving and learning how to move on the ice.

Average number of offspring: 1.

Average gestation period: 11 months.

Average weaning age: 1 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Apparently polygynous mating system. Mating occurs about the same time as weaning. Gestation, including a period of delayed implantation, lasts about 11 months. Births of single pups occur in April and early May (mainly early to mid-April). Young are weaned in 3-4 weeks, remain mostly on the ice for a few more weeks. Females becomes sexually mature at 2-4 years; many do not produce a pup until 4-5 years old; thereafter, almost all adult females give birth annually. Males are sexually mature at 3-5 years. Most probably do not live beyond 20 years.

The following is a representative barcode sequence, the centroid of all available sequences for this species.

There are 3 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 3
Species With Barcodes: 1

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

It is thought that the number of ribbon seals in the wild is increasing due to decreased hunting pressure. However, no surveys of ribbon seal populations have been completed since the mid 1970's. The largest human-created problem facing ribbon seals is the occasional accidental netting of individuals in Pacific fishing areas. (Burns, 1994; Meston, 1997; "World Conservation Monitoring Centre" website, 1999)

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: data deficient

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Population

Population Trend

Major Threats

Comments: Some drown in commercial gill nets in the Bering Sea and North Pacific. Soviet commercial harvest in the Bering Sea in the 1960s resulted in a population decline there, probably from about 80,000-90,000 to around 60,000; later, a reduced harvest resulted in a population increase. In addition to commercial hunting from ships, potential threats include industrial offshore development and overharvesting of prey species (Reeves et al. 1992).

Conservation Actions

None known.

Presently, very few are taken yearly, with those being taken for subsistence purposes by natives of the areas in which the seal lives. From the 1950's until the 1980's Russian fisheries killed large numbers of ribbon seals for their pelts, meat, and oil. Recently commercial hunting has been abandoned. (Meston, 1997)

Comments: Due to remote habitat, not regularly hunted by native peoples (but small subsistence harvest continues). Seal's lack of caution on the ice makes it vulnerable to commercial pelagic sealers. In the 1960s, the annual Soviet catch averaged about 13,000 and the population began to decline; lower quotas later resulted in a population increase (Nowak 1991).