From Texas Standard.
For most Texans, crayfish – or crawfish – come in two varieties: boiled and fried. Even in a living state, most of us probably couldn’t name too many species of mudbugs. The marbled crayfish looks like any other type, but it has one unique ability that sets it apart. The marbled crayfish can clone itself.
It sounds like science fiction, but it’s not. The tough little crustacean can take over ecosystems since it reproduces so easily, without any help from other crayfish. And while marbled crayfish are not in Texas yet, our warm climate could prove hospitable for them.
Before we consider the prolific marbled crayfish further, let’s address a question that provokes strong feelings. Do you say crayfish or crawfish? Zen Faulkes, professor of biology at the University of Texas – Rio Grande Valley, says this is one the issues “tearing the country apart.”
“People cannot agree,” Faulkes says. “On most papers in biology, I will say crayfish. In the southern U.S. most people will say crawfish. And then if you go into southern Australia, crayfish are spiny lobsters that live out in the ocean.”
Faulkes says that whatever you call them, the ability of the marbled crayfish to reproduce on its own is concerning. A hobbyist in Europe first alerted Faulkes to the phenomenon, on a crayfish message board. The hobbyist said pet owners were seeing single crayfish, alone in their tanks, having baby crayfish.
The marbled crayfish is crustacean with an extra pair of chromosomes.
“For some reason, marbled crayfish have three sets of chromosomes,” Faulkes says. “So, there’s no way you can evenly split three sets of chromosomes into sperm and egg. This animal is able to take those eggs unfertilized and they can develop into a new individual.”
This ability to quickly and easily reproduce has gotten the marbled crayfish banned in states including Missouri and Tennessee. Faulkes isn’t sure the ban will spread to other states.
“It’s tricky,” he says. “At this point they are so common in the pet trade that it would be very, very difficult to legislate against them unless you really put in a very substantial effort into education and enforcement.”
Keeping the crayfish out of the country is a moot point. They’re already here. Faulkes thinks legislation may not be an effective response.
“In a case like this it might be that really good education about pet ownership might be more effective,” Faulkes says.
The marble crayfish’s reproductive ability may have an economic benefit.
“Crayfish are big business,” Faulkes says. “In the state of Louisiana a few thousand jobs depend on crayfish. It’s a multimillion dollar industry. In China it’s 5 million jobs and a $22 billion market for crayfish.”
A crayfish that can reproduce on its own could be incredibly valuable for aquaculture purposes. They also pose a unique opportunity for scientific study.
“The fact they are so unusual makes for a lot of great scientific puzzles to solve,” Faulkes says.
Written by Jeremy Steen.