Center for Biological Diversity

For Immediate Release, September 7, 2021


Tierra Curry, (928) 522-3681,

Alabama’s Slenderclaw Crayfish Gains Endangered Species Act Protection With 78 River Miles of Critical Habitat

HUNTSVILLE, Ala.— Following more than a decade of advocacy by the Center for Biological Diversity and allies, the U.S. Fish and Wildlife Service today protected the slenderclaw crayfish as endangered under the Endangered Species Act. The tiny crayfish survives only in two creeks on Sand Mountain, near Lake Guntersville in DeKalb and Marshall counties.

“The slenderclaw is an exceptionally pretty little crayfish that needs a big helping hand from humans, so it’s great news that it finally has Endangered Species Act safeguards,” said Tierra Curry, a senior scientist at the Center. “Protecting crawdads from extinction might not sound like a priority to some, but by working to save the special animals that live in creeks, we ultimately protect rivers and our own necks.”

The Center and allies petitioned for the protection of the crayfish in 2010 and won a lawsuit in 2014 to secure a date for a decision on safeguards.

The slenderclaw crayfish is just 1.5 inches long, with cream and orange mottling. Most of the crayfish’s habitat was flooded when the Tennessee River was dammed to create the 69,000-acre Lake Guntersville in 1939. Four out of five sites within the species’ historical range are presumed to be gone, and the lake isolates the two surviving populations from one another, which reduces the crayfish’s long-term chance of survival.

The slenderclaw faces ongoing threats from silt and sediment, which fill in the spaces between rocks the crayfish uses for sheltering and harm its food sources because mayflies, caddisflies and stoneflies also need clean water. The slenderclaw is also threatened by competition from the invasive virile crayfish and by water pollution from poultry farms and other sources.

“Just working together to keep silt out of streams could save hundreds of species from extinction if agencies would prioritize stopping it,” said Curry. “When mud runs off into streams, it ruins habitat for the animals that live on the creek bottoms and ruins clear water that everyone needs for drinking, fishing and swimming. There are thousands of sources of silt into streams, but that also means there are thousands of solutions to keep it out.”

Scientists estimate nearly half of all crayfishes are vulnerable to extinction. Alabama has more species of crayfishes than any other state. Of the roughly 400 known species of crayfish in the world, at least 98 are found in Alabama. They range in size from about 8 inches for the largest, the Tennessee bottlebrush crayfish, to about half an inch for the smallest, the twisted dwarf crayfish.

Crayfish are also known as crawdads, craycrabs, crawfish, mudbugs and river lobsters. They’re considered a keystone animal because the burrows some species dig create shelter used by more than 400 other animals. Crayfish help clean the water by eating decaying plants and animals and are eaten in turn by more than 240 predators, including fish, birds, reptiles, amphibians and mammals, making them an important link in the food web.

Males court females by rubbing them with their antennae and claws. Females glue fertilized eggs onto their undersides with a sticky substance called glair. While carrying the eggs, the females are said to be “in berry” because the eggs resemble a cluster of berries. After hatching the young crayfish stay by their mother’s side for several weeks before setting out on their own. Crayfish live for two to four years.

Slenderclaw crayfish. Photo courtesy of Guenter Schuster. Image is available for media use.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.7 million members and online activists dedicated to the protection of endangered species and wild places.

center locations