Please view the main text area of the page by skipping the main menu.

Environment ministry plans to add marbled crayfish to list of invasive species

A marbled crayfish can be seen in this photo provided by the Japan Wildlife Research Center.

TOKYO -- The Ministry of the Environment on Feb. 28 informed its panel of experts about a plan to include marbled crayfish on the list of Invasive Alien Species, as they reproduce very rapidly and have the potential to disrupt Japan's ecosystem.

The crayfish is non-native to Japan and can be bought at pet shops. Based on the outcomes of a discussion by the panel, raising and importing the alien species will be banned in principle from as early as this summer.

According to the environment ministry, marbled crayfish grow to about 10 centimeters in length and are brown or blue depending on their habitat. They carry a disease that can fatally infect domestic crayfish. A huge outbreak of the species is possible as all individuals are female and reproduce by parthenogenesis, or without male contributions.

Though it is not known as to where marbled crayfish originated, they have been widely distributed in the European pet industry since the 1990s. They are also sold in pet shops and via online auctions in Japan. One marble crayfish was found in the wild in Japan in 2006 and another in 2016.

An environment ministry official stated, "Though Japan is not inhabited by marbled crayfish yet, we want to take measures before they have an effect (on the ecosystem)."

Currently, there are 148 invasive species including raccoons, snapping turtles and fire ants in Japan.

Also in The Mainichi

The Mainichi on social media

Trending