A new model shows yellow perch could be negatively impacted if bighead and silver carp were to establish in Saginaw Bay and Lake Huron.
The model showed low and high early survival rates of the carp. In the low early survival rate, it was found that 100,000 carp were needed to establish, but at the high early survival rate, just 10 carp were needed.
Lead author and researcher at Michigan State University Lori Ivan said the early survival rates of these carp are largely unknown.
“That is why we ran a variety of scenarios,” Ivan said.
One of the biggest concerns with Asian carp is how they would impact the food web and ecosystem.
Southern Lake Huron Unit Manager for the Michigan DNR Jeff Jolley has studied Asian carp over the years. He said Asian carp pose a threat to the food web.
“They're like vacuum cleaners,” Jolley said. “When you have abundant amounts of these carp, they can quickly outcompete a lot of other fish for the food they need.”
Jolley said the carp eat plankton, a primary food source for yellow perch and panfish. But these carp eat at much higher volumes than native species.
Ivan said the carp would cause the early survival rates of yellow perch and rainbow trout to drop.
Researchers said Asian carp tend to prefer warm, fast moving water when they spawn.
Research ecologist for the National Oceanic and Atmospheric Administration Doran Mason said high and fast water provides favorable odds for the eggs to hatch.
“With high water levels, you get water creating more backwater spaces,” Mason said. “Those serve as nurseries for young Asian carp.”
According to research from the Environmental Law and Policy Center, the Great Lakes basin has warmed by 1.6 degrees Fahrenheit in annual mean temperature over the last 30 years.
Mason said warming water temperatures benefits the carp by producing more habitat.
“In scenarios of potential climate change and warming of Great Lakes waters, that could potentially produce more habitat that can favor silver and bighead carp,” Mason said.
Jolley said a grass carp, another invasive species, was found in the Tittabawassee River this spring. He said it was a sexually mature fish that was capable of spawning, but it was too early in the year to know if it was going to spawn.
“We have plans to do a lot of surveying in the Saginaw River basin to see if there are anymore there,” Jolley said.
Asian carp have not successfully established in any of the Great Lakes to this point.