Diet of feral ferrets ( Mustela furo ) from pastoral habitats in Otago and Southland, New Zealand

In New Zealand, the ferret ( Mustela furo ) preys upon, and therefore could be threatening, some endemic species and may be involved in the transmission of bovine tuberculosis ( Mycobacterium bovis ) to domestic stock. The diet of the ferret was studied from prey remains in the digestive tracts of 277 live‐trapped animals from Otago and Southland. Lagomorphs constituted 77% of the diet by weight and were identified in 65% of the ferrets sampled. Other important items were hedgehogs ( Erinaceus europeus ) , possums ( Trichosurus vulpecula ) , and birds. There were no statistically significant differences in the diets of male and female ferrets except a general trend for females to eat smaller prey items. As lagomorphs are such important prey, rabbit control operations may result in short‐term increased predation on endemic species; and/or increased consumption of species that serve as a source of infection of Tb (i.e., possums and possibly hedgehogs); and/or a long‐term decline in the density of ferrets.