Perth Voice Interactive

FERAL species are still on the loose in Hyde Park with at least three whopper koi swimming free in the eastern lake.

Exotic fish often end up in local lakes courtesy of irresponsible pet owners, but koi (or ornamental carp) can cause a lot of damage to local environments and animals. One fish can lay 1.5 million eggs.

They make the water cruddier by uprooting vegetation and stirring up sediments with their vacuum-cleaner mouths, and that means native animals that rely on sight to feed can’t find a meal, and it can clog up other fish’s gills.

In high numbers they can lead to algal blooms and erosion  (since they eat all the plants near the shore).

After being alerted to the foot-long feral fish on Facebook mayor John Carey said he’d get the parks team down there to catch them.

Hyde Park’s lakes previously had trouble with the deadly red-eared slider turtle.

It was deemed so deadly (they feast on eggs and force out native turtles) the council put up a bunch of wanted signs asking people to report sightings so rangers could come down and fish them out immediately.

by DAVID BELL