Rapid decline in freshwater fish populations
By Emily Sohn, Discovery News
Sept. 1, 2009 — Just a few hundred years ago, the world’s rivers and lakes teemed with gigantic fish. Freshwater fish were so plentiful that they were used to feed farm animals and fishermen found it hard not to make a catch, according to a new review of historical accounts. Oceans get most of the attention when it comes to aquatic conservation. But the new study suggests that freshwater species have declined precipitously, too, and that conservation efforts aren’t aiming big enough when it comes to rivers, lakes and streams. “When you look at these accounts, it is pretty amazing how abundant and especially how large these fish species were that people wrote about,” said Kirk Winemiller, a fisheries ecologist at Texas A&M University in College Station, Texas. “We have a very inaccurate view of that history.” … The demise of most of the world’s grand freshwater fish, Winemiller said, was a direct result of overfishing. Today, huge lake and river fish live only in the few places in the world that are free of human influence, such as the Guiana Shield in South America. “People rarely appreciate the major impact that even a fairly moderate amount of fishing has on certain freshwater stocks,” said Winemiller, who added that the loss of big predator species reverberates throughout the ecosystem. “The impact started very long ago.” …
