Global Warming's Impact on Waterfowl, Caribou, Trout, and Bass

•For years, scientists have warned of dire impacts from global climate change--seas swallowing marshes, glaciers disappearing, spring seasons advancing by weeks. Now, in Global Climate Change and Wildlife in North America, a recent report from The Wildlife Society/National Wildlife Federation, scientists assess the likely repercussions of global climate change on ducks, big game, and more. And that could mean good and bad news for hunters and anglers.

WATERFOWL
Drier climates boost evaporation on the prairies, leaving fewer potholes. An expansion of farm acreage that's drier and more suitable for corn and soybeans could hit nesting habitat hard. That's no good for ducks. But milder winters could pump up winter wheat and fall rye crops, a bonus for birds.

CARIBOU
When green-up occurs earlier on calving grounds, caribou reproduction can rise. Although individual Arctic caribou herds in Alaska have responded differently to warming trends, higher temperatures may increase their overall numbers.

FISH
Although this report didn't crunch fish studies, other scientists predict that rising water temperatures could expand the range of warmwater fish like bass as much as 300 miles north by the middle of the 21st century. But at the same time, the shift would decrease the range of coldwater fish like trout and walleyes. One researcher from the University of Wyoming calculated that 17 percent of Rocky Mountain trout range would be lost if the average July air temperature there went up by just 1 degree Celsius--an increase that could make the water too warm for the fish to reproduce. --T. EDWARD NICKENS