Advances in New Zealand mammalogy 1990–2000: Feral ferret

MeasurementsBody, tail and hind foot lengths and body weights have been recorded in five recent studies (Table 1).They include males shorter and lighter than previously recorded.The mean head and body lengths (total excluding anus to tip of tail) given by Baker (1989) are well beyond the range of all other studies, and are considered doubtful (J.R. Ragg, pers.comm.).The weights of females are extended at each end of the previously known range.Male and female ferrets in the semi-arid lands of the South Island were heaviest in winter, and lightest in summer (Mills 1994). DistributionThere have been no extensive surveys of ferret distribution in the last forty years.There have been confirmed sightings and/or records of ferrets trapped in parts of New Zealand not included in the distribution described by Marshall (1963) and Lavers & Clapperton (1990).Ferrets are now abundant in southern Northland (Miller & Pierce 1995).They have been caught as far north as Karikari Bay and Ngataki in the far north (R. Pierce, pers.comm.).They can be found in some of the highest (600 m a.s.l.) and wettest (2500 mm annual rainfall) forests in Northland (Pierce 1996).In Taranaki, there are records from New Plymouth airport, Kapuni, and the north bank of the Mokau River, and in the following Conservation Areas: North and East Waitaanga, Makino, Hutawa, White Cliffs, Tongaporutu and Moki (L.Stanley, pers.comm.).Ferrets are found throughout the western Bay of Plenty mainland from the seashore to include all of the Kaimai and northern Mamaku ranges (J.Heaphy, pers.comm.).There have been no sightings of ferrets on offshore islands in the Bay of Plenty.Ferrets are present in the East Cape area, but their distribution appears to be patchy.Department of Conservation staff have caught numerous ferrets in coastal habitat between East Cape and Hicks Bay, but they are rarely seen between Cape Runaway and Opotiki (C.Ward, pers.comm.).Ferrets have been caught in the farming district of Ruatoria, and at Tikapa, south of the lower Waiapu River, but no ferrets have been caught along the old Motu Road, despite apparently suitable habitat and intense mustelid trapping by the Department of *49 Margaret Avenue, Havelock North.