A genus of WHALES in the family Balaenopteridae, consisting of five species: Blue Whale, Bryde's Whale, FIN WHALE, Sei Whale, and MINKE WHALE. They are distinguished by a relatively slender body, a compressed tail stock, and a pointed snout.

The species Balaenoptera acutorostrata, in the family Balaenopteridae. It is the smallest of the WHALES in the family and though mainly oceanic, is often found in coastal waters including bays and estuaries.

Large marine mammals of the order CETACEA. In the past, they were commercially valued for whale oil, for their flesh as human food and in ANIMAL FEED and FERTILIZERS, and for baleen. Today, there is a moratorium on most commercial whaling, as all species are either listed as endangered or threatened.

The species Balaenoptera physalus, in the family Balaenopteridae, characterized by a large, strongly curved, dorsal fin. It is the second largest of the WHALES, highly migratory, but rarely seen near the shore.

An order of wholly aquatic MAMMALS occurring in all the OCEANS and adjoining seas of the world, as well as in certain river systems. They feed generally on FISHES, cephalopods, and crustaceans. Most are gregarious and most have a relatively long period of parental care and maturation. Included are DOLPHINS; PORPOISES; and WHALES. (From Walker's Mammals of the World, 5th ed, pp969-70)