By Susan Milius
As Dr. Seuss noted, it’s good to have both red fish and blue fish. A new study of a salmon fishery expands on this concept, showing the importance of having lots of different red fish.
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The millions of sockeye salmon that spawn in the watershed of Alaska’s Bristol Bay each year represent several hundred distinct populations of the same species, says ecologist Daniel Schindler of the University of Washington in Seattle.
Drawing on some 50 years of records showing the annual variation in numbers of salmon there, he and his colleagues have now calculated how much the diversity of the bay’s sockeye populations matters to the long-term stability of the bay’s fishery.