Welcome to the Maine Crayfish Project

The goal of this project is to collect information on the distribution and abundance of crayfish species in Maine's lakes, streams and ponds so we can better monitor and manage the introduction and spread of non-native crayfish species. We need your help to expand our knowledge of crayfish species found in Maine!

Currently, there are 7 (or 8) species of crayfish known in the State of Maine (see list below). This represent only a small portion of over 400 species found in North America. This site provides a species key to help with crayfish identification, and informational pages for each crayfish species known to occur in Maine. If you find crayfish in your neck of the woods (corner of the cove) please let us know. We'll ask you to send us a male specimen to confirm the identification and add the information to our database. We are also interested in reports of abundant crayfish, or observations of change over time. You can also add your observations to our iNaturalist Project page: https://www.inaturalist.org/projects/maine-crayfish-project

Thank you so much for your help!

*Please refer to the species key for pictures to ease the identification process or send your samples to the University of Southern Maine to help determine distributions of native and invasive crayfish species. Please follow the specific collection protocol designed to preserve the samples for proper identification.

If you have any questions or observations regarding crayfish, please contact Dr. Karen Wilson at the University of Southern Maine. Thanks!

***IMPORTANT NOTE: Please do not release any live crayfish except where you found it. It is easy to inadvertently introduce non-native crayfish species to new habitats. Even if you think you have a native species, it may not be native to a specific lake or stream. The best way to prevent their spread is to leave them be.***