This week on Our Changing World, as part of the Summer Science series, we bring you one of our favourite conservation related episodes from the Black Sheep podcast.
Invasive: the story of Stewart Smith
Between the 1960s and late 2000s Stewart Smith went on a one-man crusade, releasing thousands of invasive fish into New Zealand’s rivers, lakes and streams.
One kind of fish he introduced is now so widespread it’s been declared an “acclimatised species”, meaning the authorities have basically acknowledged it is impossible to remove it from the wild.
"The amount of damage he did was incalculable," says science journalist Charlie Mitchell, who wrote a feature on Smith for Stuff.co.nz.
"He could be positioned alongside the people who released stoats and weasels and ferrets in New Zealand," says Bryan Winters, who wrote an authorised biography of Smith entitled That Pommie Bastard.
So who was Stewart Smith?
He was a devout communist with a stubborn streak a mile wide, a conspiracy theorist who spent years locked up in a conscientious objectors camp, and an environmental imperialist dedicated to the cause of “improving” recreational fishing in New Zealand.
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Koi carp look like goldfish when they are small, but the carp have paired barbels or feelers around their mouth which goldfish lack. The carp use their barbels and big lips to fossick for food in lake sediments. Photo: RNZ / Alison Ballance
