"We've been able to reconstruct what salmon runs looked like before the start of commercial fishing. But rather than finding a flat baseline -- some sort of long-term average run size -- we've found that salmon runs fluctuated hugely, even before commercial fishing started. That these strong or weak periods could persist for sometimes hundreds of years means we need to reconsider what we think of as 'normal' for salmon stocks," said Lauren Rogers, who did this work while earning her doctorate in aquatic and fishery sciences at the UW and is now a post-doctoral researcher with the University of Oslo, Norway.

Rogers is the lead author of a paper on the findings in the Jan. 14 online early edition of the Proceedings of the National Academy of Sciences.