Because not only are Possums nocturnal, meaning they cross roads at night when nobody can see them, but they are a PEST. They kill native birds and eat the food that native birds eat. read more
Many of those species are uniquely vulnerable to invaders, e.g. possums. To wipe out mammals on islands as big as those of New Zealand would be"a huge challenge," said Dan Simberloff, an invasion biologist at the University of Tennessee. read more
European settlers aiming to establish a wild source for food and fibre and fur pelts for clothing introduced the common brushtail possum from Australia to New Zealand in the 1850s; by the 1980s the peak population had reached an estimated 60-70 million. read more