By: A. H. Kopelman, Ph.D.
Sperm whales (Physeter macrocephalus) are the largest of the odontocetes and are also the deepest diving and longest diving of the vertebrates (138 minutes and 3000m). Sperm whales feed almost exclusively on squid but will take fish on occasion.
The 2015 best estimate of sperm whale population size in the U.S. North Atlantic Exclusive Economic Zone (EEZ) is 2,283.
As in other toothed whales, sperm whales are sexually dimorphic in size; males (36-66 ft.) are larger than females (27-56ft.). Also, as in all toothed whales, the head is asymmetrical, with a single blowhole. Sperm whales exhibit matrilineal social groups, in which most females spend their lives with close female relatives. Sperm whale males attain sexual maturity at an average of 12 years of age; females at 9 years. Sperm whale females and young remain in lower latitudes throughout much of the year. Males, generally move to higher latitudes for feeding, and will return for breeding. The matrilineal groups are quite stable, while males can interact and mate with females of other groups (i.e., other than their natal group). Old "bull" males rarely leave higher latitude and probably no longer mate.
Sperm whales are found in the waters of New York in the autumn, winter, and late spring, and occasionally during early summer. Sperm whales are listed by the IUCN (International Union for the Conservation of Nature and Natural Resources) as "Vulnerable." This means that the species (or population) is not Critically Endangered or Endangered but is facing a high risk of extinction in the wild in the medium-term future.
Information about the IUCN Red List categories and criteria.