On farmland near Waverley, New Zealand, 550 opossums (Trichosurus vulpecula) were shot between October 1968 and November 1969, and their stomach contents were analysed to find the ratio of pasture species to non-pasture species eaten. Pasture species (grass and clover) formed about 30 percent of their diet. The economic loss to the farmer, where opossums are numerous, could be considerable
A population of hedgehogs (Erinaceus europaeus L.) in pasture land in Canterbury was found to vary between less than four and eight per hectare. Feeding habits were studied through stomach contents and analysis of faeces. Grass grub beetles (Costelytra zealandica) and porina moths (Wiseana cervinta), both important pasture pests, were relatively important food items. Estimates of the number of grass grubs eaten in relation to their density and that of hedgehogs in pastures show that hedgehogs are potentially capable of consuming 10-40 percent of adult populations.
The seasonal diet of ship rats in a stand of lowland podocarp-rata-broadleaf forest in North Island, New Zealand, was studied from analysis of 173 stomachs, 46 fresh droppings and 10 feeding trials. Arthropods, particularly tree wetas (Order Orthoptera), were the main foods in spring and summer, while drupes, berries and nuts predominated in autumn and winter. Birds were not an important food. Seasonal variations in the diet were related to the seasonal abundance of these foods in the forest
Previous work on the foods of the brushtailed opossum (Trichosurus vulpecula) in New Zealand has been concerned with the choice of plants taken in indigenous bush. Although clover was sometimes recorded as a preferred food the conclusion was reached that opossums "are not grass-eating animals" (Mason 1958), and that "the opossum is not, and will never become an important grassland pest" (Howard 1963).
Most research into the diet of stoats in New Zealand has been in low altitude valleys such as the Eglinton and Hollyford Valleys. Yet much of New Zealand’s national parks (e.g. Fiordland National Park) consist of many small montane valleys and alpine areas. This research identified the key prey species of stoats inhabiting such small montane valleys and alpine grasslands.
European hedgehogs (Erinaceus europaeus) have recently been identified as a conservation threat in New Zealand. Hedgehogs were kill-trapped at 14 wetland and braided riverbed sites in the upper Waitaki Basin between late October 1997 and early February 1998 and their gut contents described. The most commonly eaten prey were Coleoptera (present in 81% of 192 guts), Lepidoptera (52%; n = 192), Dermaptera (49%; n = 192), Hymenoptera (42%; n = 192) and Orthoptera (31%; n = 319).
Impact of the irruptive fluctuation in abundance of brushtail possum populations since their initial colonisation was investigated in the forests of South Westland, New Zealand. Possum abundance, fecundity, and diet, the condition of common possum-palatable tree species, and the abundance of common forest birds were measured at three sites occupied by possums for c. 10, 20, and 30 years. Possum densities were highest at the site where possums had been present for c. 20 years.
The annual diet of possums (Trichosurus vulpecula) during both a beech (Nothofagus) mast fruiting year and a non-mast year in the simple beech forests of the North Branch of the Hurunui Catchment, eastern South Island, New Zealand, was determined by sorting the contents of 270 possum stomachs, collected between December 1999 and December 2001. Beech flowers and seeds contributed 46.1% to annual diet during the mast year, but were not eaten during the non-mast year. Beech foliage and bark made up 13.2% and 45.0% of annual diet in the mast and non-mast years, respectively.
Sympatric orange-fronted (Cyanoramphus malherbi) and yellow-crowned parakeets (C. auriceps) were surveyed in a South Island beech (Nothofagusspp.) forest during the spring and summer of 1998/99. Habitat use, behaviour and diet were recorded for each parakeet identified. A single observer did all recording. Both species were seen most frequently in the upper-most 20% of the forest stratum. Orange-fronted parakeets were seen more frequently than yellow-crowned parakeets in the lowest 20% of the forest stratum.
A poison baiting operation at Trounson Kauri Park in Northland, New Zealand using first 1080 and then brodifacoum targeted possums (Trichosurus vulpecula) and rodents (Rattus rattus, Rattus norvegicus and Mus musculus). Predatory mammals were monitored by radio telemetry during the operation. All six feral cats (Felis catus), the single stoat (Mustela erminea) and the single ferret (Mustela furo) being monitored at the beginning of the operation died of secondary poisoning following the 1080 operation.