Introduced fish (above) and native turtles (below) found in Frederick Baldwin Lake during a water health assessment.

THE discovery of three pest species of fish in Frederich Baldwin Lake in Kardinya has scientists warning they can destroy waterways.

Non-native fish species, often unwanted pets, are being dumped into natural wetland and Harry Butler Institute deputy director Stephen Beatty says they threaten native wildlife.

“Invasive freshwater fish can adapt to new environments, reproduce quickly, often becoming the dominant species in wetlands and are difficult to eradicate,” Dr Beatty says.

The fish can introduce diseases, provoke algae blooms by stirring sediments and prey on native fauna, yet Dr Beatty was not surprised to discover destructive species in the lake. 

The Harry Butler Institute is working closely with the City of Melville to restore the health of Frederick Baldwin Lake over the next year. 

In addition to removing introduced fish from the lake, researchers will also study the water quality and the environment’s ecological process, the results of which can create a model that can be used at other lakes and wetlands around Perth.

Melville councillor Nicole Robins says the project aims to ensure native species flourish and invasive species are eradicated.

“This will not only benefit our natural environment, but also lead to an increased enjoyment of the park by local residents,” she told the Herald.

A native Southwestern snake-necked turtle.

SCIENTISTS working on Frederick Baldwin’s ‘clean up’ made an exciting discovery; the Kardinya lake is home to a small population of native Southwestern snake-necked turtles.

“Finding native turtles has given us hope and we believe the lake has the potential for restoration that will help boost its turtle population and improve its condition more generally,” Dr Beatty says.

“We are very lucky that the lake is home to the southwestern snake-necked turtle,” Cr Robins says. “I am hopeful that the good work being done through this project will increase the native turtle population.”

Melville council said in a release it’s crucial for people to understand the ways they can help protect native wildlife and parks.

“When the community are educated it gives them the opportunity to contribute towards improving the water quality of our wetlands through greater awareness of their impact on our local environment,” the council said. 

Park-goers can help by reporting sightings of unusual looking species of fish in waterways to Fishwatch on 1800 815 507 or through the PestWatch app. Additionally check the City of Melville website for more information on the Frederick Baldwin Lake project and how everyone’s actions can contribute.

by LIV DECLERCK