Natural Decline To Extinction Of A New Zealand Rabbit Population

Abstract

     Early introductions of rabbits (Oryctolagus cuniculus) to New Zealand in 1834 failed, but liberations of Silver-grey and wild type from 1862 to 1868 spread. Most of South Island was occupied by1880 and North Island by 1900.  During the initial expansion, rabbits became established in marginal habitats such as alpine grasslands and montane valleys.  Those in Nelson Lakes National Park originated partly from Silver-grey stock in Nelson about 1865.  In the early 1900s they were present above the tree-line at 1500 m, and on the Travers Valley floor at 600 m.  The alpine population apparently did not survive long, but three pockets of rabbits in the Travers Valley remained in 1960.  One became extinct about 1964; one was watched carefully for a week each month, declining gradually from 26 rabbits in November 1963 to nil in January 1966; and the third became extinct in the early 1970s.  A combination of poor habitat, predation, isolation, and competition from hares (Lepus europaeus) seems responsible.