Possums are now estimated to number 70 million in New Zealand, and are acknowledged as a pest that inflicts colossal damage on New Zealand’s indigenous flora and fauna. However, only 100 years ago, they were highly valued and strictly protected.
Possums were introduced to New Zealand with the intention of establishing a fur trade. They were first released in the 1830s, but initially failed to become established. Imports began to taper off after 1900, and until the late 1930s, they were periodically protected as imported game – it was illegal to trap or kill them. As David Young notes, they were regarded by the government as “furry money-spinners” well into the third decade of the 20th century.
The damaging effects of possums on indigenous flora were not unknown even in the early 20th century, but it was not until Les Pracy and Ron Kean’s definitive report of 1949 that these effects became well-known and accepted.
There is now little debate about the devastating effects of these voracious eaters – they consume an estimated 21,000 tonnes of vegetation a night. They can cause the complete collapse of a forest canopy – especially of “possum favourites”, such as rata and kamahi. Possums are omnivorous and also eat the eggs and chicks of native birds (and, sometimes, adult birds).
Today, an immense amount of effort and money goes into attempting to control possums using traps or poison, which is the responsibility of both central and regional government. However, it is an uphill struggle that is unlikely to cease any time in the near future.
Sources: Te Ara Encyclopedia of New Zealand and Our Islands, Our Selves, by David Young
Photo above: Two possum trappers with a day’s catch from the Lake Waikaremoana district. Not to be reproduced without the permission of Alexander Turnbull Library, ref. PAColl-8983-05