Researchers from Purdue University have made some unsettling discoveries regarding Asian carp.
“It looks like the carp can probably become established in a wider range of environmental conditions than once thought,” said Reuben Goforth, an assistant professor of forestry and natural resources.
Goforth and associates learned that the exotic invaders are spawning in waters previously thought too narrow or slow moving. That means even more sport fisheries are at risk.
On a semi-positive note, he added, ‘’While the presence of eggs indicates a successful spawning of these fishes in new areas, it’s not known yet whether those eggs would be successful in surviving to adulthood.”
Additionally, they found evidence of carp spawning far upstream and eggs drifting in water as late as September in Indiana’s Wabash River. Previously, reproduction was thought to end in July.
Until now, most information related to where Asian carp might spawn was based on data gathered from their native habitats in Asian rivers and streams.
“The reason truly invasive species are so successful is because they overcome obstacles,” Goforth said. “When you base their limitations on what happens in their native ecosystems, it’s a good start. But it may be a good idea to go back and take this new data to recalculate more precise limits based on these new understandings.”
Support Grows for Separation
Those who want to protect the Great Lakes from Asian carp invasion by removing the manmade connection between Lake Michigan and the Mississippi River basin have a new ally.
Illinois Gov. Pat Quinn surprised many when he endorsed that solution during a meeting with other governors here.
“Ultimately, I think we have to separate the basins,” he said. “I really feel that is the ultimate solution. We have to do it.”
Chris Kolb of the Michigan Environmental Council called Quinn’s remarks “a very positive step forward.” And Michigan Gov. Rick Snyder said, “I think it’s great to see people talking about longer-term solutions.”
In the past, Illinois sided with Indiana, the city of Chicago, and the Obama administration in opposing the separation. They argued that closure would increase flood risks, while damaging tourism and commerce.
“It’s important that we deal with this issue, but it’s also important that we deal with it in a way that preserves the logistical advantage and opportunity to move commerce through the region,” said Indiana Gov. Mike Pence.
But Michigan, Wisconsin, Minnesota, Ohio, and Pennsylvania have long favored the strategy and even sued the U.S. Army Corps of Engineers and Chicago’s water district. In a suit they lost, they claimed that refusal to separate the watersheds created a public nuisance.
The strongest argument for closing the aquatic highway, though, is that an explosion of Asian carp in the Great Lakes could decimate the system’s fishery, worth an estimated $7.5 billion annually. Additionally, the connection leaves the way open for other invasive species to cross watersheds.
The connecting canal was constructed more than a century ago, to allow Chicago’s sewage pollution to flow downstream, instead of contaminating the city’s Lake Michigan water supply. It also allowed for commercial navigation.
(These articles appeared originally in B.A.S.S. Times.)