Radio-tracked rodent surprises researchers

摘要

Invasive rodents,particularly rats,have been observed to disrupt severely the ecosystems of confined territories such as islands.A paper by biologists in Auckland,New Zealand,published in Nature for 20 October,describes experiments using a free-ranging Norway rat(Rattus novvegicus).Rats can be eliminated from islands but often reinvade.At least 11 islands in New Zealand have been reinvaded by this rat species since 1980,and in the early stages elimination is difficult.