Invasive cloning crayfish found in Burlington pond

Published August 4, 2023 at 12:21 pm

The marbled crayfish can threaten other species native to Ontario.

A crayfish that can rapidly reproduce on its own and push out other species has been found for the first time in Canada in a Burlington pond.

Ontario’s Ministry of Natural Resources and Forestry reports the marbled crayfish was found in the pond at City View Park (Dundas St. E. and Kerns Rd. area) this summer.

Common in aquariums around the world, this is the first one to have been found in the wild in Canada.

The ministry is concerned about the marbled crayfish because it can threaten native species by overtaking natural settings through its ability to rapidly reproduce.

“Because the marbled crayfish does not require sexual reproduction, a new population can become established in a new area with the release of only one individual,” the ministry reports in a bulletin. “It is an all-female species which reproduces through clones that are genetically identical to the mother without the need for sperm or a fertilized egg. They are found to survive in many different environments, including countries with climates like Ontario.”

It is believed the marbled crayfish found its way into the pond by being released from an aquarium.

“Because it is not native to Canada, someone releasing it is the likely reason,” a representative from the ministry said. “The person probably didn’t realize the threat it poses.”

It’s not known how it was discovered.

The ministry is investigating the occurrence to see if the crayfish is spreading.

If they become established in Ontario, according to the ministry, they could replace native crayfish, which are already being impacted in parts of Ontario by the invasive rusty crayfish.

“Marbled crayfish have generalist diets that can lead them to overconsume aquatic vegetation. They may also impact Ontario’s biodiversity by feeding on algae, plants, invertebrates and amphibians,” according to the bulletin.

Abundant numbers of these crayfish may also destabilize shorelines through the creation of their burrows on riverbanks.

If you spot a marbled crayfish you can contact toll-free Invading Species Hotline at 1-800-563-7711 or report it online or with your mobile device using  EDDMapS

inhalton's Editorial Standards and Policies advertising