BROWNSVILLE, Texas (ValleyCentral) — An invasive species of crayfish was collected by researchers from the University of Texas Rio Grande Valley at the first known site in Texas.
Between January and February, three of the Australian Redclaw Crayfish (Cherax quadricarinatus) were collected at an apartment complex pond that connects to a nearby resaca in the Brownsville area, Texas Parks and Wildlife said in a news release.
In 2013 a sighting of a female crayfish of this species with several young was also identified on iNaturalist, indicating the species has been present at this location for some time.
According to the release, the Brownsville sighting is just the second detection of this species in the wild in the United States with the other being in California.
Texas Parks and Wildlife Department Aquatic Biologist Dr. Archis Grubh surveyed numerous sites in the area in July and found three additional Australian Redclaw Crayfish between the apartment pond and a nearby resaca 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,” Grubh said. “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.”
According to researchers, the potential for reproduction is a concern in these waterbodies since both male and female Australian Redclaw Crayfish have been collected. The reason for this concern stems from the fact that the species can reproduce prolifically.
A female Australian Redclaw Crayfish can brood up to five times a year at 1,000 eggs per clutch, the release stated.
Australian Redclaw Crayfish grow rapidly and can reach maximum size, up to two pounds, in under a year. These large crayfish can significantly alter habitat and vegetation, competitively exclude native crayfish, and impact native fish communities by direct predation.
Australian Redclaw Crayfish can also carry “Crayfish Plague,” a contagious fungal disease affecting freshwater crayfish, as well as other parasites/diseases that could impact native species.
Australian Redclaw Crayfish, along with all other members of the crayfish Family Parastacidae, are prohibited exotic species in Texas and cannot be legally purchased, sold or possessed in aquariums, the release states. It’s also illegal to release these crayfish into a public waterbody.
Sightings of Australian Redclaw Crayfish should be reported to TPWD by emailing photos and location information to firstname.lastname@example.org.