SEI WHALE

also called Rudolphi's Rorqual (Balaenoptera borealis), swift baleen whale of the family Balaenopteridae. The sei whale is usually about 13 to 15 m (40 to 50 feet) long and is bluish gray or blackish above and paler below. It has small flippers, about 50 short lengthwise grooves on its chest, and dark baleen with paler, silky, inner fringes. The sei inhabits oceans from the Arctic to the Antarctic, migrating between cold and temperate summer waters and winter breeding grounds in warmer regions.