Crayfish of Alabama

Alabama has 100 documented crayfish species, recorded since scientific collecting began in the mid-1800s [1]. The authors estimate it may have 10 to 20 more. Crayfish live in nearly every freshwater habitat, including caves, springs, creeks, rivers, swamps and bogs, and are often the largest invertebrate group in these systems. A 2022 book, Crayfishes of Alabama, summarized the work. See Biodiversity of Alabama.

Habitats and burrowing

Primary burrowers live in burrows connected to groundwater rather than surface water, often in fields or floodplains, and some burrows are over 13 feet deep with chimneys up to 10 inches tall. Secondary burrowers dig along stream edges. Tertiary burrowers live in permanent waters and burrow only when surface water recedes [1].

Cave species

Alabama has eight stygobitic species that are largely eyeless, pale and long-antennaed. All occur in the cave-rich Tennessee River valley, and three are known from single caves [1]. See Caves of Alabama.

The Fall Line

The Fall Line is the main geographic boundary affecting distribution: 45 species are found almost only above it, 42 almost only below it and 13 on both sides [1]. See Geography of Alabama.

Endemics by drainage

Eight endemic species are in the Tennessee River system, which holds nearly half the state’s crayfish species while draining about 13 percent of its land, and seven are in the Mobile River basin, which drains about 61 percent of the state and holds 59 species [1]. See Rivers of Alabama.

Threats and conservation

Threats include wastewater, runoff, sedimentation, dams and mining. The article calls invasive species the most significant threat: the virile crayfish, first found in Alabama in 1953, has spread across north and central Alabama, probably through bait, and the Kentucky River and gray-speckled crayfish were found in 2013 and 2014. The Geological Survey of Alabama worked about 17 years with Guenter Schuster and Christopher Taylor to identify species and their conservation status [1].

Diversity

Alabama has 100 documented crayfish species. The 2022 book Crayfishes of Alabama described 99 species and 11 hypothetical ones; one was later confirmed in Sumter County, and the authors estimate 10 to 20 more may exist. Fifteen species are found only in Alabama, 8 in the Tennessee River system and 7 in the Mobile River basin. Nine genera are mentioned, including Cambarus, Procambarus, Faxonius, Orconectes and Hobbseus.[2]

Habitats

Crayfish live in caves, springs, creeks, rivers, reservoirs, seasonal ponds, marshes, swamps, bogs and ditches. Burrowing species are grouped as primary, secondary or tertiary. Forty-five species occur almost entirely above the Fall Line, 42 almost entirely below it and 13 on both sides. Eight cave-dwelling species occur, all in the Tennessee River valley, and eight are fully adapted to cave life.[2]

Threats and the book

Pollution, agricultural and forestry runoff, habitat destruction and dams are cited, but the main concern is non-native species. The virile crayfish was first found in 1953, likely spread as bait, and the Kentucky River crayfish (2013) and gray-speckled crayfish (2014) are also invasive. The book, published by University of Alabama Press in 2022, resulted from about 17 years of research by the Geological Survey of Alabama with Guenter A. Schuster and Christopher A. Taylor.[2]

FAQs

How many crayfish species does Alabama have? 100 documented.

How many are endemic? 15.

What is the biggest threat? Invasive crayfish introduced as bait or with fish stocking.

Sources

1. Encyclopedia of Alabama: Crayfishes of Alabama
2. Encyclopedia of Alabama: Crayfishes of Alabama

Editorially reviewed by Specialty Digest Editorial TeamLast reviewed November 10, 2026Researched and drafted with AI assistanceReport an issue