Distribution and Habitat
The ribbon seal resides in North Pacific and Arctic waters, in particular the Sea of Okhotsk and Bering Sea. They associate with pack ice between January and May, but are believed to be pelagic during the rest of the year.
Adult ribbon seals average 155-165 cm in length and 70-80 kg in weight. They may grow to 190 cm and 100 kg. Newborn pups are 80-90 cm long and 9-10 kg in weight. The darker of the animals pictured above is a typical male, and the lighter a typical female. Newborn pups have long, white hair that is moulted to the juvenile coat with blue-grey dorsal and silver-grey ventral colouration. Females are reported to be sexually mature at 2-5, and males at 3-6 respectively. gestation lasts 10.5-11 months and the pregnancy rate is reported to be 85%. Life expectancy is 22-26 years. The diet is primarily fish, as well as cephalopods and invertebrates.
Abundance is not well known, but estimates are generally on the order of 200,000-250,000.
Threats to the Species
Some commercial prey species (e.g. pollock, Theragra chalcogramma) are important components of ribbon seal diet, and some ribbon seals are caught incidentally in commercial fisheries. Proposed petroleum exploration in parts of their range and they are legally hunted. The largest hunt is in Russia, and overexploitation has been a problem in the past.
Reijnders, P. et al. 1993. Seals, Fur Seals, Sea Lions, and Walrus. Status Survey and Conservation Action Plan. IUCN Seal Specialist Group. Gland, Switzerland. 87pp.
Rice, D.W. 1998. Marine mammals of the world: systematics and distribution. The Society for Marine Mammalogy Special Publication Number 4. 231 pp.