Exam MSC111-Nekton

  1. Advantages to size and mobility
    • access to higer volume for foraging
    • specialized niches
    • ability to utilize patchy prey
    • ability to select different habitats for different stages of life history
  2. New Technology to study animals...
    • Time-Depth Recorders
    • Acoustical tags
    • Satelitte tags and GPS
    • Attached cameras
  3. Osteichthyes
    • -bony fish
    • -skeleton made of bone
    • -Swim bladder to regulate boyancy
  4. Types of fish body shapes
    flattened, elongated, laterally compressed, irregular (seahorse)
  5. Warning Coloration
    dangerous, bad tasting, poisonous
  6. Cryptic Coloration
    blend with the environment, hide from predators, stalk prey
  7. Disruptive Coloration
    break up outline of individual fish to confuse predators
  8. Dark Top, light bottom, camoflauge in open water
  9. Sharks that bite pieces from large prey
    •Tiger shark – Diverse stomach contents

    •Great white shark – Wound and wait

    •Cookie cutter shark – Cut out chunks
  10. ingest smaller prey whole
    Nurse shark (benthic vertebrates)
  11. Filter Plankton (gill rakers)
    •Whale shark – Warm

    •Basking shark – Cold

    • •Megamouth
    • shark

    •Manta ray
  12. bony fish feeding
    a.Capture large prey whole



    • b.Pickers - Ingest smaller prey
    • whole

    •Butterflyfish, Slipmouth

    • c.Grazers
    • •Parrotfish
    • •Filefish
    • d.Filter plankton – Gill rakers
    • •Anchovies
    • •Sardines
    • •Herrings
  13. Anadromous
    • spawn in fresh water, spend most of life in ocean
    • Ex. Salmon
  14. Semelparous
    Die after giving birth, Advantages are the eggs have a higher chance of survival
  15. Homing facto
    enabled by olfactory imprinting
  16. Catadromous
    • Spawn in oceans, spend most of life in freshwater
    • Ex. eels

    •Spawn in Sargasso Sea (400-700 m or deeper)


    •Eggs hatch into leptocephalus larvae

    •Larvae spend a year or more as plankton then undergo metamorphosis into juveniles

    • •Adults spend 10-15 years in fresh water before migrating to
    • Sargasso Sea to spawn
  17. A. Pinnipeds
    Marine Mammals

    • •apparently entering the ocean to take
    • advantage of the new and abundant food resources created by an upwelling of
    • colder, nutrient-rich waters along the coasts of Europe and North America.

    • • phocid seals (earless, or true, seals) and the otarioid
    • seals (eared seals and walruses) diverged from a bearlike or doglike common
    • ancestor about twenty-five million years ago. (interestingly, the skulls of sea
    • lions, bears, and such canids as large dogs and wolves are nearly
    • indistinguishable at first glance.)
  18. Pinnipeds (seals etc)
    • eat squid and fish
    • predators are sharks, killer whales and polar bears
  19. Grey Seals
    damage fishing nets im attempt to eat caught fish
  20. Threats to sea lions and seals
    oil spills, algae blooms, habitat loss, competition, removal of seals
  21. Carnivora
    Sea otters-smallest marine mammal, no blubber layer, keystone predators in kelp, voracious

    Polar Bears- semi aquatic, feed primarily on seals through air holes in ice, affected by climate change
  22. Sirenia
    • Manatees, Seacows, dugongs
    • strictly vegetarian, front flippers, swim mostly with tail, threatned by coastal development and boats
  23. Cetacia
    whales, dolphins, porpoises

    • •Streamlined for efficient swimming
    • •Example of convergent
    • evolution
  24. Mysticeti (baleen whales)
    • includes largest animal on earth, blue whale
    • baleen made of kariten
    • squeeze water through baleen and lick of remaining food
  25. Odontoceti (Toothed Whales)
    a.Sperm whales – 3 species

    •Sperm, Dwarf Sperm, Pygmy Sperm

    • •Bulbous head contains spermaceti (waxy substance) that may
    • function in buoyancy and sound generation

    • •Sperm can dive to 3000 m and stay
    • under water for up to two hours!

    • •Feed on fishes and squids, esp.
    • giant squids

    •Produce ambergris, undigested material in stomach

    b.Toothed whales – 30 species

    • •Beaked, Beluga, False Killer,
    • Narwhal, Orca, Pilot

    •Most common in cold water

    • c.Dolphins & Porpoises – 33
    • species

    •Distinctive beak

    •Travel in pods

    • •How do they
    • sleep?
Card Set
Exam MSC111-Nekton