Electrofishing technology is being utilised to keep Auckland's Western Springs Lake pest-free.

Electrocurrents are being used to stun pest fish and turtles so they can be scooped up, brought to land and killed, with no native species being harmed in the process.

Auckland Council senior freshwater ecologist Matthew Bloxham says too many people are getting rid of their old pets when they become inconvenient - with many dumping them in Western Springs.

"These things become enormous and they're incredibly fecund animals, they're breeding machines. We call them habitat modifiers...what we're trying to do at Western Springs is give the natives a chance." 

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