Poison with purpose

IT IS SOMETIMES controversial and sounds counterintuitive, but the poison 1080, developed in Europe in the 1940s to kill rodents, is proving to be one of the most effective tools available for biodiversity conservation in Australia and New Zealand.

Without 1080 it’s likely the extinction lists for both countries would be considerably longer – by dozens of species. To appreciate how this scenario has come about it’s important to understand some particular quirks about the nature of life on these two island nations, brought about to a large extent by their long geological isolation.

Significantly, the vertebrate fauna of both countries has evolved largely without much pressure from predators. Australia has a few marsupial carnivores but none as voracious as the mammalian predators in many other countries. And New Zealand has only two native species of land-dwelling mammals. Both are bats.

This meant that when an introduced predator such as the European fox () landed in Australia – deliberately brought by early European settlers – many native mammals didn’t stand a chance. To make them even more vulnerable, a large proportion were the perfect size, at weights of between 50g and