An aggressive species of Australian crayfish has somehow made its way into the Yarkon River in central Israel and could pose a major threat to the semi-terrestrial crabs known to reside there.
The red claw crayfishes were discovered by the River Authority and Nature and Parks Authority last week after hikers reported seeing a large crab near the river.
“We used special traps for river crabs and, to our dismay, we found 10 crayfish,” Dr. Dana Milstein, an aquatic ecologist for the Nature and Parks Authority told Haaretz. “All of them were found up-river, in the less polluted part of it.”
The Australian breed of crayfish were first seen in the Kinneret four years ago, but according to Milstein, "the Yarkon is the first water source in which it has managed to settle down."
Scientists posit the crayfish could disrupt the ecosystem in Tel Aviv's Yarkon Park by attacking and competing with local species as well as adversely affect efforts to preserve the river.
Ecologists, meanwhile, speculate the crayfish in the Yarkon were dumped there by someone who grew tired of his crustacean pets.
The red claw crayfish is legally imported to Israel. While a popular pet for fish tank owners, it can often prove problematic because of the danger it poses to other animals.
“What was he thinking?” Yarkon River Authority director David Pergament asked on Wednesday. “That he could get rid of his problem by causing harm to a place people visit and walk in?”