An invasive species of crayfish is spreading through Texas waters, sparking grave wildlife concerns for conservationists.
Researchers in Brownsville, Texas, have been investigating reports of an Australian red claw crayfish, a crustacean that typically belongs 8,000 miles away, after the species was seen pervading southern Texas waters, specifically the Rio Grande Valley.
The Rio Grande is a free-flowing natural river located in the southernmost tip of Texas that spans roughly 4,200 square miles across four counties. Around 196 miles of the river, which was designated by Congress in 1978 as “the Rio Grande Wild and Scenic River,” meanders through stretches of breathtaking desert and canyons of stratified rock.
Texas Parks & Wildlife officials are concerned that the crayfish species is spreading quickly, causing havoc by outnumbering other native species that exist in the same water.
The Australian red claw is a large-bodied crayfish, distinctively recognized by its blue-green body with red and maroon highlights. When fully grown, the crustacean can reach a total length of around 10 inches and can weigh up to 1.3lb, according to the National Oceanic and Atmospheric Administration.
Typically, they can be found in tropical and subtropical climates, coastal streams, and freshwater environments, and favor slower-moving upper reaches of rivers as well as lakes and lagoons, according to experts.
Researchers in Brownsville, Texas, have been investigating reports of an Australian red claw crayfish in the Rio Grande Valley (Instagram/@texasparkswildlife) At present, there are over 400 crayfish species that inhabit waters in the U.S. – a total that amounts to roughly 70 percent of the world’s total species, according to Virginia State University.
Speaking on a PBS show aired Sunday about the concerns, University of Illinois crustaceans expert Chris Taylor, said: “The biggest threat that we know of for native crayfish species are invasive crayfish coming into new habitats and actively displacing them.”
Taylor added that one of the goals of the biological project in Brownsville was to “assess that threat”.
“You can’t overstate how important crayfish are. They are prey source for fish species, mammal species, [and] birds,” said University of Illinois aquatic ecologist Dusty Swedberg.
“Everything is interconnected and [if] you start to lose some of those middle pieces in a food web, it’s going to have an impact somewhere else”, Taylor added.
Researchers have been monitoring the risk of competition that the invasive species poses to the native crayfish revealing that they were trying to see “where they are, how many are there, [and] if they’re successfully reproducing.”
Texas Parks and Wildlife invertebrate biologist Archis Grubh said he was expecting to find at least “50 to 100” after researchers waded through the river.
However, he remained positive stating there were “not as many in the resacas as I was expecting, so I think that’s a good sign.”