Researchers recently announced the discovery of over 7,000 grass carp eggs in a Lake Erie tributary. The good news? This isn’t the Asian carp species we’re trying to prevent from entering Lake Michigan. The bad news? Grass carp carry a different threat.
Asian carp is a catch-all term for 4 different species of invasive carp – black, grass, silver, and bighead.
Silver and bighead carp eat plankton that native fish populations need to survive. Grass carp feed on vegetation. Nicole King at the University of Toledo’s Lake Erie Center says that could be dangerous for wetland restoration.
“Wetlands are a really important habitat for lots of different fish, birds, reptiles, and amphibians,” explained King.
“If these grass carp reach high enough numbers, they could potentially have some serious effects on these wetlands.”
King is part of a multi-agency effort focused on managing the grass carp population in Ohio’s Sandusky River. They include organizations in Michigan, Ohio, and Canada.
Rich Carter works for the Ohio Division of Wildlife. He says that in addition to removing the grass carp eggs, they are also learning about the life history of the species.
“We’re looking at not only where they’re spawning and what conditions trigger spawning, but we’re also looking at opportunities to capture the fish,” said Carter.
Carter says they used electrical currents in the water to stun fish and Trammel nets to capture them.
Unlike efforts to prevent silver and bighead carp from ever reaching the Great Lakes, this plan is to help limit grass carp. “It’s really an issue of potential to manage this species that’s been in the system for what we know is a number of years and reproducing in the system,” said Carter.
King says grass carp have been found in the watershed of every Great Lake except for Lake Superior.