Invasive Australian Redclaw Crayfish Found in Texas
Eugene L. 08.18.22
University of Texas Rio Grande Valley researchers recently collected invasive Australian Redclaw Crayfish (Cherax quadricarinatus) from the first known site in Texas. From January to February, three Australian Redclaw Crayfish were collected from an apartment complex pond that is connected to a canal in the Brownsville Area.
Australian Redclaw Crayfish have been identified in this location before, there being a sighting back in 2013. That original sighting was a sighting of a female crayfish with several young indicating that the species has been in this location for some time now. This is the second section of the crayfish in the wild in the US with the first detection being in California.
Texas Parks and Wildlife Department (TPWD) Aquatic Biologist Dr. Archis Grubh surveyed numerous sites in July in the same area and found three more of these invasive crayfish between the pond and a canal two miles away.
“We don’t know when these invasive crayfish were first introduced or how far they have spread, but we do know they can have a negative effect on local species and biodiversity,” said Grubh. “Spreading the word about this invasive species and reporting sightings to TPWD can help us better understand where it is distributed and potentially take steps to help prevent its spread.”
With both male and female Australian Redclaw Crayfish having been collected, the potential for reproduction is a concern. This species can reproduce prolifically, which in other nations makes it a popular choice for aquaculture and pet trade. They grow quite large quickly and are capable of reaching up to two pounds in size. They are capable of significantly altering the habitat and vegetation of waters and can outcompete smaller native crayfish. So the potential for damage to our native ecosystem is high.
Australian Redclaw Crayfish, are a prohibited exotic species in Texas and cannot be legally purchased, sold, or possessed in aquaria. It is also illegal to release them into a public waterbody.
“Release of aquarium life is unfortunately a key means by which invasive species such as these crayfish are introduced,” said Monica McGarrity, TPWD Senior Scientist for Aquatic Invasive Species. “Well-meaning, uninformed aquarium owners sometimes release their pets thinking they’re doing the best thing for them, but if they do survive, they can become invasive and harm the native aquatic species and ecosystem. Aquarium owners should research alternatives to aquarium dumping and help prevent introductions of the next invasive species.”
Sightings of Australian Redclaw Crayfish should be reported to TPWD by emailing photos and location information to [email protected].