The council also provided a list of numbers of pest animals killed or trapped for the period January 1 to June 30 this year.
Possums were by far No 1 at 3489, followed by goats (215), hares (146), deer 131, rats (109), feral cats (45), pigs (32), stoats (3), weasels (2) and hedgehogs (1).
Despite the possum number, the council said it was difficult to identify a single plant or animal pest as being the “biggest problem” across the district “as pest impacts vary considerably between locations, habitats, land uses and community values”.
“Different species can present different challenges in different areas, and priorities may change over time.
“The council therefore takes a risk-based approach to pest management that is aligned with legislative requirements and informed by community and stakeholder input.
“The council also monitors for emerging pest threats and places a strong emphasis on preventing the establishment and spread of new pest species within the region, as early intervention is typically the most effective and cost-efficient management approach.”
Meanwhile, the Department of Conservation (DoC) has extensive information on possums on its website.
The animal, introduced from Australia in the 19th century during an unsuccessful attempt to start a fur trade, has had a significant impact on New Zealand ecosystems.
“Leaves are the main part of their diet, but possums are opportunistic omnivores and eat native birds and their eggs, land snails such as Powelliphanta and invertebrates, including wētā.
“They eat buds, flowers, fruit/berries and nectar, which means they compete with native birds and reptiles for food sources. The growth and life cycle of a tree or plant is significantly affected when all parts of it are eaten.”
The animals also nest in holes used by birds like kākāriki and saddlebacks.
Farming is also affected.
“Dairy and deer farmers have the added worry of possums spreading bovine tuberculosis. The value of economic loss in primary production for damage and control of possums is in the tens of millions.”
It has also been confirmed possums are eating kea on the West Coast.
“Researchers using nest cameras have witnessed the gruesome reality inside defenceless kea nests invaded by stoats and possums in South Westland.”
DoC said if people wanted to help fight possums, they should access the Predator Free 2050 information and resources on its website.