Polar Ecosystems

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Polar Ecosystems

• The Arctic Marine Ecosystem the Arctic Ocean is
  relatively small and shallow much of area
  includes continental shelves high productivity
  in N. Pacific and N. Atlantic
• Greenland Sharks large shark, scavenger high
  amount of pollutants in blood (incl. PCBs, Agent
  Orange)
• Arctic Cod relative of true cod main prey of
  seals and dolphins
• Cetaceans
• Narwal males with single long tusk, used in male
  battles for dominance
• Beluga gregarious white whale high-frequency
  vocalizations
• Bowhead whale eats copepods remains in polynyas
  through winter
• Pinnipeds
• Several species, including Ringed, Harp, Bearded,
  Ribbon, and Spotted seals
• Walrus males with pair of long tusks haul-outs
  along rocky shores
• Polar Bear catch ringed seal pups on the ice
  during two-week period between birth of pups and
  ice break-up global warming has led to earlier
  ice break-ups (threatened listing, United States
  E.S.A.)

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Figure 14-29
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Polar Ecosystems

• The Antarctic Marine Ecosystem the Southern
  Ocean surrounds the continent of Antarctica
  nutrients churned up from the melting of ice in
  southern Spring (cold, dense water sinks) ? high
  productivity krill most important zooplankton
• Invertebrates echinoderms, sponges, cnidarians
  dominate seafloor coverage sea spiders common
• Antarctic Icefishes (Notothenioids) possess
  anti-freeze proteins in blood important food
  source for penguins, Weddell seals
• Cetaceans Blue, humpback, minke, and killer
  whales
• Pinnipeds
• Leopard seal large, powerful predator (of
  penguins)
• Crabeater seal teeth modified for straining
  krill
• Weddell seal southernmost seal remains through
  winter and grinds down teeth maintaining
  breathing hole
• Southern elephant seal males fight for dominance
  (? beachmaster)
• Birds male emperor penguins balance egg on feet
  through winter, other species (ex. chinstrap
  penguin) breed in summer skuas

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Figure14-30