Keystone Interactions: Salmon and Bear in Riparian Forests of Alaska

  title={Keystone Interactions: Salmon and Bear in Riparian Forests of Alaska},
  author={James M. Helfield and Robert J. Naiman},
The term “keystone species” is used to describe organisms that exert a disproportionately important influence on the ecosystems in which they live. Analogous concepts such as “keystone mutualism” and “mobile links” illustrate how, in many cases, the interactions of two or more species produce an effect greater than that of any one species individually. Because of their role in transporting nutrients from the ocean to river and riparian ecosystems, Pacific salmon (Oncorhynchus spp.) and brown… 
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