Sick Fish May Get Sicker: Climate Change and Other Stresses Expected to Affect Entire Populations of Fish

Entire populations of North American fish already are being affected by several emerging diseases, a problem that threatens to increase in the future with climate change and other stresses on aquatic ecosystems, according to a noted U.S. Geological Survey researcher giving an invited talk on this subject today at the Wildlife Disease Association conference in Blaine, Wash.

“A generation ago, we couldn’t have imaged the explosive growth in disease issues facing many of our wild fish populations,” said Dr. Jim Winton, a fish disease specialist at the USGS Western Fisheries Research Center. “Most fish health research at that time was directed toward diseases of farmed fish.”

In contrast, said Winton, recent studies in natural aquatic systems have revealed that, in addition to being a cause of natural death, infectious and parasitic fish diseases can produce significantly greater mortality in altered habitats leading to population fluctuations, extinction of endangered fish, reduced overall health and increased susceptibility to predation.

In addition, said Winton, populations of certain fish species have suffered catastrophic losses after non-native diseases were first introduced into a water body. Examples include whirling disease in the intermountain west and the recent introduction of viral hemorrhagic septicemia in the Great Lakes.

To read full report, go to USGS.