Trophic Cascades in a Formerly Cod-Dominated Ecosystem

  title={Trophic Cascades in a Formerly Cod-Dominated Ecosystem},
  author={Kenneth T. Frank and Brian Petrie and Jae S. Choi and William C. Leggett},
  pages={1621 - 1623}
Removal of top predators from ecosystems can result in cascading effects through the trophic levels below, completely restructuring the food web. Cascades have been observed in small-scale or simple food webs, but not in large, complex, open-ocean ecosystems. Using data spanning many decades from a once cod-dominated northwest Atlantic ecosystem, we demonstrate a trophic cascade in a large marine ecosystem. Several cod stocks in other geographic areas have also collapsed without recovery… 

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