Monday, November 27, 2006
We all hear about the bad effects that dams have on fisheries. This article in Scientific American says that in some cases a fishery can be "improved" by a dam.
"Dams destroy habitat and prevent fish from reaching their spawning grounds. Even artificial fish ladders to help facilitate migration are a poor second to the real thing.
Dams also change water temperature and regulate river levels and flows for agriculture or industry -- all of which can have negative consequences on the local marine life.
Still, some see a new fishery as being better than none at all if a dam is deemed necessary for flood control, water supply or hydro power. "We generally favor the native fish but we recognize that there are situations where a tailwater fishery can provide recreational and economic benefits," said Williams.