2023-2024 Invasive Crayfish Collaborative Webinar Series

This webinar series will explore how agencies, universities, and other organizations are working to control the spread of invasive crayfish within the Great Lakes. If you are concerned about the impacts of invasive crayfish or are interested in the techniques used to control them, join us as we examine species-specific actions, advancements in research and technology, and programs designed to help communities prevent and manage invasive crayfish populations. A question and answer period will follow each presentation.

Upcoming Webinars in this Series

Production of neofemales to increase available tools for suppressing invasive crayfish populations

Friday, December 8, 2023, 3:00pm to 4:00pm CT

A variety of techniques have been employed to suppress or eradicate populations of invasive crayfish, including chemical control agents and baited trapping and removal. However, there is growing desire to develop species-specific control measures that limit effects to off-target organisms, which can be used to augment existing eradication techniques. PhD student Katie Eaton from Auburn University will discuss one emerging method that involves a simple manipulation to the sex determination system. Juvenile male crayfish can be sex-reversed in the lab using a technique called RNA interference. These “neofemale” crayfish, when mated with normal males, will produce broods that are 100% male. By introducing neofemales into invasive populations on a regular basis, managers can, over time, skew the sex ratio of these non-native populations, eventually leading to complete or near-complete eradication.

Recorded Webinars in this Series

An Overview of Michigan’s Invasive Red Swamp Crayfish Response (recorded on 11/13/23)

Red Swamp Crayfish (RSC) were first detected in Michigan waters in the summer of 2017. Since then, they have been found in eight distinct population complexes. Following the initial detection, Michigan Department of Natural Resources, Michigan State University, and other partners have trapped and removed close to 200,000 RSC and have conducted innovative pesticide treatments. Monitoring data were collected to evaluate the effectiveness of treatment strategies. Dr. Brian Roth from MSU and Kathleen Quebedeaux from MDNR will give an overview of Michigan’s control and monitoring strategies and will evaluate the impact of their efforts.

Development of Multiple Control Techniques for Red Swamp Crayfish in Surface Waters and Burrows (recorded on 10/25/23, 63 minutes)

In collaboration with a multi-agency research team funded by the Great Lakes Restoration Initiative, researchers at Auburn University have used laboratory and pond studies to develop and evaluate potential control techniques for Red Swamp Crayfish in surface waters and burrows. Control approaches range from carbon dioxide to physical blockers to plain old hot water. In this webinar, Dr. Jim Stoeckel and his graduate student Nick Barnes from Auburn University will present results of previous and ongoing studies and discuss strengths and weaknesses of each approach.

Food Web Impacts of Invasive Red Swamp (Procambarus clarkii) and Rusty (Faxonius rusticus) Crayfishes in the Chicago River and Lake Michigan (recorded on 10/12/23, 64 minutes)

Invasive crayfish can disrupt the natural balance of aquatic ecosystems, often by outcompeting native species and altering trophic relationships. Dr. Reuben Keller from Loyola University Chicago will share his work on the food web impacts of two invasive crayfish species in the Chicago River and Lake Michigan, the red swamp (Procambarus clarkii) and rusty (Faxonius rusticus) crayfishes.