Evaluation of the Reproductive Status of Ctenopharyngodon Idella in Western Lake Erie

Invasive grass carp (Ctenopharyngodon idella) were first introduced into the United States in 1963 as a biocontrol agent and have since been released.  Recently, multiple individuals have been captured in the Laurentian Great Lakes. While the overall extent of their impact is not fully known, grass carp pose a significant risk to native fisheries populations. Their feeding on submerged aquatic vegetation destroys food sources, shelter and spawning areas vital to native species. Even though grass carp are bred as triploid, diploid individuals have been previously reported in Lake Erie. With both diploids and triploids being captured in the western basin of Lake Erie, the extent of the population that is reproductively viable has yet to be delineated. In this study, grass carp captured by commercial fishermen in Michigan waters of Lake Erie were sampled to determine the reproductive status of this population. Twenty nine individuals were screened between May and October 2014.  Their ploidy was determined via a BD FACSAria 2 flow cytometer.  These data are being used to determine the ploidy status of current populations within western Lake Erie. These data will enable management to understand the extent of the current invasion and determine means to manage population expansion.