The habitat use and movements of a population of Australian, brush-tailed opossums, Trichosurus vulpecula (Kerr), were studied by live-trapping, spotlighting and radiotelemetry in a mixed pasture, bush and scrub habitat on Banks Peninsula, New Zealand. Resident opossums had distinct ranges that for some animals varied in position and size and, for all, varied in intensity of use of habitat types during the year. Seasonal foods and breeding behaviour were reasons for shifts in ranges and changes in their sizes.
The stomach contents of 34 opossums collected from Otari reserve, Wellington, New Zealand, were examined and fragments of leaves and leaf cuticles were identified. Leaves were the main food though flowers, fruit and at least one insect were also taken. The main species eaten were kohekohe (Dysoxylum spectabile), pohuehue (Muehlenbeckia australis), hinau (Elaeocarpus dentatus), climbing rata (Metrosideros fulgens), five-finger (Pseudopanax arboreum), tawa (Beilschmiedia tawa) and lawyer (Rubus cissoids)
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
Agouti grey pelage, as found in the opossum and many other mammals, is a generalised concealing coloration. In dense vegetation melanic pelage also is concealing, but the melanic phase displaces the grey one in rain forests where, in the current absence of predation, selection is not for colour. This local dominance suggests close linkage of genes for melanism with ones for toleration of humidity.
Three different models of bovine tuberculosis (Tb) in brushtail possums were evaluated against their stated purpose, and testable assumptions and predictions evaluated against available data where possible. Not surprisingly, two of the models may be falsified based on currently available data with respect to either important model assumptions or predictions, and the third may suffer from being right for the wrong reason. This does not mean that these models are not useful.
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.
Introduced rodents and possums in New Zealand eat flowers, fruits, seeds and seedlings, but little is known about their impact on forest regeneration. We investigated seedling establishment in exclosures with mesh of two different sizes to exclude (1) possums and (2) possums and rats, at two mainland forest sites (beechpodocarpbroadleaved and second-growth broadleavedpodocarp) near Dunedin. We recorded all new woody seedlings that established over the next 2 years.
The contribution of seeds and fruit to the diet of the introduced brushtail possum (Trichosurus vulpecula) was examined in seral vegetation in lowland Canterbury, New Zealand. Fruit and seeds comprised c. 70% of total possum diet, and possums contributed 17% of the dispersed seed rain for the period of our study. The effect of gut passage on germination was measured for five seed species by germinating seeds recovered from faeces of captive and wild possums. At least one-quarter of seeds of four of the species germinated.
The condition of 79 plants of the loranthaceous mistletoe Tupeia antarcticain a podocarp-hardwood forest in the central North Island, New Zealand, was monitored over 4 years during a period of increasing possum density, following previous possum control. Mistletoe comprised 1.2% of total possum diet during the three years following possum control. Incidence of possum browse on mistletoe plants increased from 2.6% of plants when the trap-catch index of possum density was < 3%, to 75.9% of plants when trap-catch rates reached 4.6%.