This article is from the Dolphin
FAQ, by Jaap van der Toorn
Cetaceans is a collective term for whales, dolphins and porpoises. The name is derived from the scientific (Latin) name of these animals: Cetacea.
4.8 - Are whales and dolphins endangered?
For most species, the answer is probably "No", although it is very difficult to get a good estimate of the size of populations on these water living creatures. A number of species are endangered: the Indus river dolphin, the baiji (there are only about 100 left), the vaquita, the northern right whale and the blue whale. Another group of species is listed as "vulnerable" (which means that they are not in immediate danger of extinction, but also far from safe). These are: the Ganges river dolphin, the boto, the bowhead, the southern right whale, the sei whale, the fin whale and the humpback whale.
M. Klinowksa (1991) Dolphins, Porpoises and Whales of the World The IUCN Red Data Book IUCN, Gland, Switzerland and Cambridge, U.K.