By RAY GARCIA
Capital News Service
LANSING — Plankton are the preferred food of silver and bighead Asian carp, two of the four main Asian carp species threatening to invade the Great Lakes.
It’s a food source in decline in the carps’ current breeding areas. But the fish are still finding lots to eat, making them a greater threat to extend their range, according to a recent study.
These carp eat algae, mussel excrement and many other non-living organic materials, according to a study by scientists at the the University of Michigan and National Oceanographic and Atmospheric Administrattion. It appeared in the journal “Freshwater Biology.”.
The carp are also capable of fasting for long periods and traveling long distances, said Peter Alsip, a data analyst at the Cooperative Institute for Great Lakes Research in Ann Arbor, who led the study. That could be bad news for the Great Lakes.
The fish don’t appear overly dependent on plankton and likely wouldn’t suffer if it isn’t around.
“If [Asian carp] chose to go out there, they could mitigate their weight loss and manage their weight loss by feeding flexibly on these different prey items throughout the water column,” Alsip said.
The carp prefer shallow water but can journey through deep water to find better areas for food and breeding. They are in the Illinois River, which leads to Lake Michigan through the Chicago area.
“They’re not going to necessarily reside there, as these fish will probably want to seek out areas with more food,” Alsip said. “These off-shore areas might just serve as migration corridors for the fish as they seek out these more food-rich waters.”
Preventing the movement of the carp is crucial to keeping them from getting into the Great Lakes, where fishing is a $7 billion-a-year industry. They could wreak havoc to the ecosystem, as the carp take food from native fish and other aquatic life, he said.
“When you consider the possibility that these fish can feed on different prey types and feed at different depth, that really re-enforces the importance of investing in prevention,” Alsip said.
Ray Garcia reports for WKAR Radio and Great Lakes Echo. A version of this story originally aired on WKAR Radio.