Food Webs in the Wake of Atlantic cod

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Food Webs in the Wake of Atlantic cod

• Present is not the key to the past
• How might coastal ecosystems have changed since
  cod extirpation

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Whats known and knowable about Atlantic cod?
Monhegan I., Maine 1880s

• They were big predators
• Had broad trophic latitude
• Were abundant
• Lived in coastal benthic habitats
• Strong interactors (controlled the structure of
  food webs)

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(No Transcript)
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Fish bones in Indian kitchen middens 500 -
2,500 years ago
Archaeological site in Boothbay Harbor, Maine
Carlson 1986
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Coast of Maine
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Penobscot Bay
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Average percent fragments from all strata
Atlantic cod
Flounder total
Sea mink
Fish unidentified
Winter flounder
Softshell clams
Swordfish
Sculpin
Sturgeon
Yellowtail flounder
Tomcod
Harbor seal
Seal (unidentified)
Grey seal
American dab
400 - 4500 ybp
Dogfish
Cunner
Herring
Blue mussel
Haddock
Halibut
Pollock
wolf fish
Sand flounder
Salmonids
American Eel
Sea urchin
Harp Seal
Alewife
Waved whelk
Quahod
Carchardon (great white)
Plocaena (porpoise)
Cusk
Balaena ( Right)
Mackerel
Bluefish
Spies Lewis 2001
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Years bp
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No lobster or crabs?
Years bp
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Cod Size Over Past 4500 years
5000
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Fishing Grounds of Coastal Maine 1830 - 1880
(Goode 1887)
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Cods Prey
Prey
Echinoderms
Sand and rocks!
Langton Bowman 1980
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40 cm