Histriophoca fasciata
ribbon seal

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. (Burns, 1994)

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. (Meston, 1997)

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. (Burns, 1994; Meston, 1997)

Ribbon seals live about 20 years in the wild. (Burns, 1994; Meston, 1997)

The presence of standing ice is very important to H. fasciata during the winter and spring months. They will rest on the ice, often very far from the water. Ribbon seals seem to be unconcerned with the threat of predation, as they will allow their young to wander far from the mother's location for long periods of time. Individuals tend to be solitary; females will shelter their pups however. As ice begins to melt in the late summer some populations will move further north with the receding ice-line. Most populations become pelagic in the summer months. Little is known about the feeding behaviors of H. fasciata, but they most likely dive for food in ways similar to other seals. One characteristic that is different in H. fasciata when compared to most other seals is the method of locomotion on ice. The ribbon seal will slither along the ice using side-to-side motions to propel itself, rather than inching forward with the front flippers as do other seals. (Burns, 1994; Meston, 1997)

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. (Burns, 1994; Meston, 1997)

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)

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)

Histriophoca fasciata have an interesting structure on their trachea, the anterior portion is connected to a large air-sac. This sac is present in both sexes, although it is much larger in males. There is no similar structure in any other species of seal, and its function is unknown. (Burns, 1994)