Crayfish ‘trapping’ doesn’t control invasive species
Oct. 13 (UPI) — In Britain, a handful of celebrity chefs have encouraged the practice of crayfish “trapping” to control the invasion of American signal crayfish.
Unfortunately, new research — published Tuesday in the Journal of Applied Ecology — suggests the practice doesn’t work. In fact, crayfish trapping can have a host of unintended consequences.
“Trapping has been linked to a range of risks to our waterbodies, including the spread of invasive species on wet or unclean equipment, as well as the direct capture and release of invasive crayfish to seed new harvestable populations,” study co-author Eleri Pritchard told UPI in an email.
“Sadly, trapping also risks protected native wildlife, and has been responsible for the deaths of otters and water voles,” said Pritchard, a postdoctoral researcher at University College London.
American signal crayfish have led to significant declines of native crayfish in Britain and Europe. The invasive species is a carrier of what’s called crayfish plague, a disease that is lethal to the native white-clawed crayfish. American signal crayfish are also bigger and more aggressive than native species, outcompeting them for available resources.
Beyond threatening native species, American signal crayfish also burrow into stream banks, undermining natural stream structures and increasing flood risks. Researchers suggest the invasive species also poses a threat to fish, invertebrates and aquatic plants.
Taking a cue from efforts to curb the spread of invasive fish species, chefs in Britain have encouraged people to trap and eat American signal crayfish.
“Crayfish trapping involves the use of funnel traps, very similar to lobster pots,” Pritchard said. “The traps are submerged in the water and baited with something to attract the crayfish, like fresh oily fish or cat-food. This entices the crayfish through the funnel entrances of the trap and once inside, it is difficult for them