Fauna

Flora

Introduced species

Prior to human arrival in New Zealand the only mammals present were three species of bats. However, since human arrival, about 900 years ago, at least 31 species of mammal have established as wild or feral populations in New Zealand.^[16] The kiore (Rattus exulans) first arrived with the early Polynesians, and another three species arrived during European settlement between 1770 and 1890. Stoat (Mustela ermine), weasel (M. nivalis) , and ferret (M. furo) were released in the 1880s in an attempt to control rabbits (Orycto-lagus cuniculus). Domestic cats (Felis catus) also arrived in New Zealand as a result of European settlement. The introduction of these species has caused native birds species in New Zealand to dramatically decline.^[16]

Victoria Forest Park is predominantly made up of beech forest, which are important conservation reserves for endemic birds, and in the summers following heavy seeding of the beech trees, which occurs every 4–6 years, insect, mouse (Mus musculus), and stoat numbers increase rapidly.^{[12][17][18][19]} When the beech forests experience a high seed year, it results in a population pulse of the house mice which then results in the population pulse of the stoat (King and Powell 2011). When there is an abundance of food available for the stoat, they are able to produce larger litters and with the stoat being the most common mammalian carnivore in South Island beech forests, conservation managers prepare for heavy seedfall as a period of increased conservation hazard in beach forests. In beech forests, mohua, kaka, robins, bellbirds and blue ducks are all at risk of being predated on by stoats post seed fall irruptions^[16][19]

Significantly increasing the risk to New Zealand birds is the fact that the majority are hole nesting birds and don’t possess the predator avoidance mechanisms that other introduced species possess and so they are more vulnerable for the following reasons:

• They nest in holes with only one entrance meaning the incubating adult is not able to escape when a predator enters.
• Predation results in a biased sex ratio as only the females incubate.
• Native birds incubation period is longer than most introduced bird species
• Native bird chicks are more noisy on the nest, attracting the attention of predators ^[16]

Mining

The town of Reefton, located on the western edge of Victoria Forest Park, was founded as a gold and coal mining town in the 1880s. As such, mining relics can still be found throughout the park. Some mining is still being carried out within the Victoria Forest Park. In 1993, GRD Macraes was granted permission for a mine footprint of 107ha and were authorised a pit, tailings dam and a waste rock stack. Since then, the mine footprint has been extended to170ha. GRD Macraes have made numerous other variation applications to increase the scale of the footprint and production which have been refused.^[23] In April 2014 the park gained public attention with the Government allowing new oil and gas exploration permits in the park.^[24]

Pest Management

The restoration of New Zealand’s mainland ecological communities has been extremely challenging. The use of aerial and bait station poisoning for rats and possums and kill-trapping of mustelids has been attempted in many mainland forests. This has resulted in increased breeding success of native bird species. Poisoning of stoats rather than trapping has the potential to greatly reduce the cost of controlling stoats as fewer visits to the area are required and because stoats are difficult to trap and it has been identified that secondary poisoning of stoats in South Island beech forest could be an effective means of control.^[26][27] In a study by Alterio (2000) on the use of 1080 and brodifacoum for controlling rodents such as rats and mice, secondary poisoning of stoats and cats was found to be significant and so this could be an especially useful way of restoring New Zealand mainland ecological communities. However, it is necessary that poisoning is carried out in a way that it will not have any impacts on non target native species.^[27]

Hunting

No mammal species that has been introduced to New Zealand is afforded any type of protection. Therefore, there are few restrictions on recreational hunting of introduced mammals apart from getting permission of the landowner to gain access to the land. Pest managers see recreational hunting as a reasonably useful control method but recreational hunting tends not to maintain low enough densities of their target species to protect the more vulnerable species.^[16]