Grass Carp Egg Sampling in Known Spawning Tributaries and Beyond

Abstract

"Invasive Grass Carp (Ctenopharyngodon idella) have been captured in all the Great Lakes except Lake Superior. The first spawning was confirmed in 2015 in the Sandusky River, a tributary to Lake Erie. We identified other potential Great Lakes spawning tributaries and prioritized sampling rivers with regional fishery managers. Eight tributaries have been monitored for Grass Carp early life stages through 2023. Grass Carp eggs were collected in the Maumee and Huron (OH) rivers (Lake Erie) in 2017 and 2022, respectively. Conversely, no eggs were found as part of expanded sampling in the Cuyahoga, Grand, or Portage rivers (Lake Erie), Tittabawassee River (Lake Huron), or St. Joseph River (Lake Michigan), however, continued monitoring is needed due to imperfect detectability. Information on the timing and location of Grass Carp spawning has improved the ability of management agencies to target removal and control, while maintaining surveillance of other potential spawning tributaries.

Presenter: Ryan Brown, University of Toledo"