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16.2: Marine Vertebrates

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    Taxonomy of marine vertebrates include:



    (have prominent canine teeth)
    FAMILY Mustelidea Sea otters Among the smallest of marine mammals, range: North Pacific, largest member of the weasel family. Each carries a pebble tool to break open shells.
    FAMILY Ursus • Polar bears Live in the arctic circle, primary diet of seals, lives on ice, snow, open ocean.
    FAMILY Pinnipeds
    GENUS • Walruses Range is in the Arctic and subarctic in Northern Hemisphere on continental shelves. Large tusks and whiskers used for foraging for bivalves on seabed.
    GENUS • Seals Fin-footed ( flippers ), semi-aquatic marine mammals, 33 extant species worldwide.
    GENUS • Sea lions Sea lion have external ear flaps, long fore flippers, the ability to walk on all fours, and are voracious eaters. Six species worldwide, except N. Atlantic.
    GENUS • Fur seals

    Similar to sea lions (smaller), 1 species in North Pacific, 7 species in S. Hemisphere; have external ear flaps, long fore flippers, ability to walk on all fours.

    Examples of Marine Carnivores
    Otter Polar bear walrus Colony of Walruses
    Figure 16.3. Sea otter Figure 16.4. Polar bears Figure 16.5. Walrus Figure 16.6. Walruses on ice.
    Monk seal Steller sea lion Steller sea lion colony fur seals
    Figure 16.7. Monk seal Figure 16.8. Steller sea lion Figure 16.9. Steller sea lion colony Figure 16.10. Fur seals


    (Aquatic herbivores living in coastal areas)
    FAMILY • Manatees (tropical Atlantic Ocean)
    FAMILY • Dugongs (Indian and western Pacific Oceans)
    Examples of Sirenia
    Manatees Dugong
    Figure 16.11. Manatees Figure 16.12. Dugong
    ORDER Cetacea Cetaceans have elongated skull with blowholes on top, use echolocation: they emit
    click-like noises and get return—used to detect fish, and can be used to stun fish. Cetacea have large brains relative to body size; can communicate with each other, many are considered trainable.


    Toothed whales:
    FAMILY • dolphins (Delphinidae) - seven genera with about 40 species, worldwide
    FAMILY • porpoises (Phocoenidae) - Compared with dolphins, porpoises have shorter beaks and flattened, spade-shaped teeth.
    FAMILY • killer whales (technically a subfamily of dolphins, called "blackfish" or orcas - 6 species)
    FAMILY • beaked whales (have prominent noses [or nose -like features] - 22 species)
    FAMILY • Sperm whales - largest of the toothed whales, 3 species, (They use echolocation to hunt giant squid.)


    Baleen whales (Baleen is fibrous plates in whale mouths used to sieve prey items.)
    FAMILY • Right whales (Balaenidae): 4 species live in northern oceans, mostly North Atlantic
    FAMILY (1species) • Rorquals whales (9 species, worldwide), includes:
    * Blue whale - largest of all mammal species - up to 30 m (98 ft), 180 tons
    FAMILY • Humpback whales (1 species) - found in all oceans
    FAMILY • Gray whales (1 species) - live in coastal waters of the Northern Pacific only
    Examples of Cetaceans
    Dolphin Porpoises killer whale narwhales
    Figure 16.13. Dolphin Figure 16.14. Porpoises Figure 16.15. Killer whale Figure 16.16. Narwhales
    Sperm whale Blue whale Humpback whale Baleen whale
    Figure 16.17. Sperm whale Figure 16.18. Blue whale Figure 16.29. Humpback whale Figure 16.20. Atlantic right whale (baleen showing)

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