NATURAL HISTORY

KILLER WHALE } Orcinus orca
FAMILY: Delphinidae

Orcinus is derived from the Latin word orcus, which means “of the netherworld.” Originally known as “whale killer,” the orca's common name stems from early whalers' records of the species' predatory behavior.

DESCRIPTION: Killer whales are perhaps the most striking cetaceans in the world, with black bodies and distinctive white markings on their chest and sides and a conspicuous white patch slightly above and behind the eyes. They have large, rounded pectoral fins and a unique, variable gray or white “saddle patch” behind their large dorsal fin. While females are smaller than males, full-grown adults can reach 25 feet in length and weigh 10,000 pounds.

HABITAT: Killer whales may be seen in all types of marine ecosystems but prefer cooler temperate and polar regions. Although sometimes spotted in deep water, they are usually partial to coastal areas.

RANGE: Killer whales are found in all of the world's oceans and most seas. The Southern Resident population makes its home in the international inland waters of Puget Sound, Juan de Fuca Strait, Haro Strait and Georgia Strait, occasionally visiting California in winter.

MIGRATION: These whales spend their summers in Puget Sound; in recent years they’ve been seen off the San Francisco coast and in Monterey Bay in winter.

BREEDING: Female killer whales become mature at 15 years of age. Mothers calve, with a single offspring, about once every five years until they’re 40. All resident pod members, including males of any age, participate in the care of young. Killer whales are presumed to be polygamous, but do not breed within their own pods.

LIFE CYCLE: Male killer whales generally live 35 years in the wild. Females are longer lived, averaging 50 years with some individuals living past 80.

FEEDING: Sometimes called the “wolves of the sea,” killer whales often hunt in packs and feed on a diverse array of species, including fish, seals, sea turtles, sharks and other species of whales. While other populations prey mostly on marine mammals, the southern resident killer whales of Puget Sound subsist largely on Chinook salmon.

THREATS: The stresses and dangers faced by Puget Sound killer whales are many. Toxic chemicals, declines in salmon, general ecosystem deterioration, growing whale-watching pressure, collisions with ships, oil spills, Navy sonar, and entanglement in fishing nets have pushed this population into decline.

POPULATION TREND: Southern resident killer whales have experienced alarming population instability during the past 30 years, indicating that the population is unsteady and oscillating toward extinction. Since 1996 the population has experienced a steep drop, going from 97 to 78 whales. According to a viability analysis conducted by the Center, if the current population decline continues, the Puget Sound population will go extinct within 100 years — and possibly as soon as 30.

Photo courtesy Flickr/Miles Ritter