biological control of possums
CONTEMPORARY BIOLOGICAL ISSUE ESSAY. ... Since the 1940s possums have been a pest and now occupy about 95% of New Zealand. Possums causes extensive damage to indigenous forests and are the major vector or carrier of bovine Tb to cattle and deer. Forest ecosystems are being drastically altered by the selective attention of possums that can eliminate favoured species from a whole forest. Possums also prey on birds. Currently about $45 million is spent annually on eradicating possums. However, this level of expenditure is not sustainable and traditional methods of control are becoming less socially and politically acceptable, some reasons for this are that they kill non target species for example deer and are expensive as they require many man hours and applications. The most common methods of controlling possums are poisoning and trapping The most widely used traps are cage traps and timms traps.