HOUSTON – So what are these mutant marbled Crayfish, or as we say here ... marbled crawfish?
These freshwater critters are part of an all-girls crowd. They produce their own eggs all by themselves.
No mating with males is needed. Within each black egg they produce is a carbon copy of themselves.
The hatchlings are only daughters and they are all clones of their mothers.
“The marbled crayfish have three sets of chromosomes,” explains UT Rio Grande Valley biologist Zen Faukles, who studies marbled crayfish.
“They can't split three sets of chromosomes into mom's contribution and dad contribution, so they reproduce asexually,” Faulkes said.
How did this happen?
“Accidentally, like so many things in biology,” Faukles said. “In most animals, we have two sets of chromosomes and you get half from mom and half from dad … they can’t divide up there chromosomes in the same way we do.”
How often do they reproduce?
They will reproduce their whole lives.
How big do they get?
They get to be any where between 4 to 6 inches.
Where are they in the wild?
Right now, Faulkes said, they are in Europe and Madagascar -- they’re causing problems.
Crayfish like to eat everything so when they are introduced to a fresh water system they can wreak havoc. Faulkes said they bury themselves in river banks and they can make river banks slide. They also can cause trouble for rice paddies.
In certain sport fishing areas in Europe, Faulkes said they have caused the fishing to dry up.
Are they here in Texas?
Faulkes said right now, they appear to be only in Texas in aquariums as people's pets. Faulkes said it needs to stay that way. If anyone releases them into the wild, they multiply so fast it could wreak havoc.
“Never, ever, ever do that,” Faulkes said. “You are not making food for fish. You are contributing to ecological catastrophe.”
Can marbled crayfish mate with males?
No, Faulkes said. They can do the deed with males but they will not produce any offspring. Marbled crayfish will only generate eggs from themselves and their offspring will be clones of themselves.