Ringed Seal (Phoca hispida)
Reference work entry
Ringed Seal (Phoca hispida) – a pinniped animal of the seal family (Phocidae) and one of the smallest and most common seal. The body length is usually 110–140 cm; the largest animals reach 150 cm in length. They gain the maximum weight in autumn and winter, when most of the animals (adults) reach 40–80 kg. Males of this species are only slightly larger than females. The general coloring is slightly variable individually from light silver to dark gray. The coat is relatively thick and long, and R.S. skin is not only used as raw rawhides, but also for sewing fur products. R.S. is very common in the Arctic Ocean, mainly in its marginal seas and seas of the northern parts of the Atlantic and Pacific Oceans, where ice is available even in winter. Most of the year, R.S. tends to coastal waters, especially to those with embayed coasts and islands. R.S. does not migrate for long distances. In summer, R.S. keeps mainly in coastal waters and sometimes forms small aggregations on the rocks or gravel spits. In autumn, as the sea freezes, most of the animals leave the coastal zone for the depths of the sea and occupy fast and drifting ice. The greatest aggregations of ringed seals are observed in spring on the drifting ice during molting, mating, and giving birth to pups. Most often R.S. is in grouped by 10–20 animals, but there could also be clusters of hundreds or more animals. They remain on the ice until it disappears. Cubs are born on the ice from late February to early May, depending on the area. The length of a newly born cub is about 50 cm and weight about 4.5 kg. A cub, covered with white fur, is born on ice, often in the snow hole. It has thick, long (2–2.5 cm), soft milky white fur or slightly grayish in color, which remain unchanged for about 2–3 weeks (whitecoat). Milk feeding lasts about a month, and this time young seals do not go into the water. Sexual maturity occurs for some females in the fourth year of life, for the majority in the fifth year; the majority of males become sexually mature at the age of 5–7 years. The water depth for R.S. does not matter, because the main food for them is fish. The composition of the food is very diverse: various crustaceans and common fish – capelin, saffron cod, and smelt. R.S. does not do any significant harm to fisheries. R.S. is of significant commercial value.
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