Zoology A Closer Look: Orcinus orca

Discussion in 'Zoology' started by pineappleupsidedown, Nov 30, 2004.

  1. pineappleupsidedown

    pineappleupsidedown Premium Member

    Common name:
    Killer whale, Orca

    Scientific Classification:
    Phylum Chordata
    Subphylum Vertebrata
    Class Mammalia
    Order Cetacea
    Family Delphinidae
    Genus Orcinus
    Species orca

    Basic Information

    Orcas are the largest member of the dolphin family, Delphinidae. Males grow to a maximum length of about 32ft (9.8m) and weight of 10 - 11 tons (9 - 10,000 kg) Females are smaller and grow to a maximum length of about 28ft ( 8.5m ), weighing as much as 7 -8 tons (6,500 to 7,500 kg). Calves at birth are about 8ft (2.4m) long and weigh about 400lbs (180 kg).

    Orcas are highly social whales, travelling about in discrete social units called pods. The relationships within the pod are stable and may persist from one generation to the next. Each pod contains one adult male, several adult breeding females and a number of sub-adults of both sexes. Pod size may vary from as few as four to as many as forty. Small pods, which are split off from larger ones, are less stable and may die out within a generation, probably because the larger pods monopolize preferred food resources. The orcas hunt together, and this behavior accounts for the evolution of the social links that result in pod formation.

    Killer whales are versatile predators. They feed on a wide variety of species, ranging from fish to warm-blooded prey such as birds, seals or even other whales. They require 2.5 to 5 percent of their body weight in food each day. making access to a substantial and reliable food source important. Fish and squid probably make up the bulk of their diet, with some pods (see Behavior and Social Systems) specializing in warm-blooded prey. Methods for feeding on squid are unknown, but when hunting in packs the whales trap and atack prey simultaneously.

    There is only one species of orca, however geographic isolation may have created different unique races and populations. Near the Washington, British Columbian and Alaskan coasts we know that there are at least two distinct races of orcas. These are referred to as Transients and Residents. Even though these two groups share the same ocean space they differ in their social habits, range, diet and to some extent even their physical appearance. In recent years a third population, the Offshores, has been discovered living along this coast. Not much is known about this group, as sightings have been infrequent. We do not know if they represent another unique race or another community.

    Not yet, but many people are worried that the Orca soon will be, or that it SHOULD be on there already.
  2. Bleys

    Bleys Phoenix Takes Flight Staff Member


    Nice piece there Pineapple! Orcas are one of my favorite ocean creatures.

  3. pineappleupsidedown

    pineappleupsidedown Premium Member

    There you go Bleys, pictures of one of your favorite animals.

  4. red cell

    red cell New Member

    Yeah killer whales are awesome did you know there are some that live of the coast of argentina? Also some familys of Orcas hunt different food and hunt different ways. Also they seem to comunuicate with each other when hunting seals, schools of fish, and any other difficult to hunt prey.
  5. mscbkc070904

    mscbkc070904 Premium Member

    As like most living organisms, what we learn about an animal and its patterns will change thru evolutionary periods due to environment changes, food source, and compromise of habitat. Soon in time, Orcas along with many other various whales will be in places they normally are not. Just like Giant squid washing up on California beaches when most are found deep south in the Pacific.