Crayfishes of Georgia
Crayfishes of Georgia Overview List of Georgia Species Species Lists by Drainage Crayfish Identification Keys by Drainage Ecology and Life History Links and Other Useful Information Glossary



Welcome to the Crayfishes of Georgia webpage.  This is a work in progress so please check back often to look for updates.  At this point, nearly all of the species accounts are completed.  The dichotomous keys are finished but read warnings on the key page.  Please get in touch with me if you find mistakes or have ideas of ways to improve the site.  Thank you for visiting.

Introduction to the Crayfishes of Georgia

Crayfishes are freshwater decapod crustaceans that live in a variety of aquatic habitats worldwide.  They are related to better known decapods such as lobsters, crabs, and shrimps.  Crayfishes are found on all continents except Africa and Antarctica and are most common in North America.  Of the approximately 550 species found on earth, over 400 live in North America with the southeastern United States being center of global diversity.  We see this same pattern of  biodiversity with other temperate aquatic organisms such as freshwater fishes and mussels.  The other area with a major crayfish fauna is Australia with approximately 120 species.

Georgia is home to approximately 70 species of crayfishes which ranks it fourth in diversity behind Alabama (~90 species), Mississippi (~80), and Tennessee (~90).  Seventeen of the Georgia species occur nowhere else in the world.  This is another pattern that we find throughout the crayfish world—crayfishes exhibit high rates of endemism.  Endemic means to live in a certain area and many crayfishes inhabit only a very small area. 

The crayfish fauna of Georgia is well known because of the seminal work of Dr. Horton H. Hobbs Jr. titled The Crayfishes of Georgia (Hobbs 1981).  Dr. Hobbs is considered the father of American crayfish work and described about 60% of the Georgia fauna as new species and over 40% of all the species found in North America!  The Crayfishes of Georgia has been out of print for a long time but is now available online as a pdf (see Links).  This volume contains beautiful illustrations and is full of detailed information on geographic variation within species; it is a must for the serious student of Georgia crayfishes.  It is also an invaluable reference on species that are more widespread and found in adjacent states. 

Little work on Georgia crayfishes has been conducted since Hobbs (1981). However, in 1996, Taylor et al. published a paper describing the conservation status of all the crayfishes in the United States.  In that paper, they suggested that many of the species in Georgia are imperiled.  Because of this assessment and a follow-up paper published in 2007 (Taylor et al. 2007), the state of Georgia listed 20 species as protected within its borders (GADNR 2006).

There is still much to learn about Georgia crayfishes.  Nearly every time I go collecting I find something new such as a range extension or some detail of a species’ life history not previously recorded.  I encourage you to photograph crayfishes that you find and send me the locality information so I can update the distribution maps for various species.

This project was funded in part by a State Wildlife Grant provided by the U.S. Fish and Wildlife Service and administered by the Nongame Conservation Section of the Georgia Department of Natural Resources.  Additional funding was provided by Georgia College and The Environmental Resource Network (T.E.R.N.).

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