In 1865, rabbits were released on a remote New Zealand island as emergency food for shipwreck survivors; they survived for 127 years and developed distinctive traits

In October 1865, rabbits were deliberately released on Enderby Island, a remote island in New Zealand’s subantarctic Auckland Islands, with a practical purpose: to provide a potential source of food for people who might become stranded there after a shipwreck. The rabbits, brought from Australia, established a breeding population and survived for the next 127 years in an environment very different from the conditions in which domestic rabbits were normally kept.

Enderby Island is the northernmost island of the Auckland Islands group, where cold, wet and windy conditions made survival difficult for introduced animals. With no regular human management, the rabbits adapted to the island and, over generations of isolation, developed characteristics that distinguished them from mainland wild rabbits.

A population shaped by isolation

According to New Zealand’s Te Ara encyclopedia, drawing on material from the Department of Conservation, the rabbits were probably descended from British silver-grey rabbits. During their 127 years on Enderby Island, they developed into a distinctive population with a silver-grey coat and a dark slate-blue undercoat.


The animals were generally moderate in size, weighing about 2 kilograms. Their heads, ears and tails were darker than the rest of their bodies and could sometimes appear almost black. Their unusual appearance was one of the characteristics that later made the population scientifically and genetically significant.

The island’s isolation had effectively separated the rabbits from other rabbit populations for generations. What had begun as an introduced food source had therefore become a genetically distinctive population living in a harsh subantarctic environment.

Conservation priorities came into conflict

The same isolation that made the Enderby rabbits unusual eventually contributed to a difficult conservation decision. By the late 20th century, New Zealand authorities were working to remove introduced mammals from the Auckland Islands because of their effects on native vegetation and wildlife.

The rabbits were not simply considered an introduced species that needed to be removed. They also represented a distinctive population for which no other known wild population existed. Conservation authorities therefore faced two competing priorities: restoring the island ecosystem and preserving the genetic characteristics of the Enderby rabbits.

The rabbits' burrowing behaviour was another concern. A 1995 IUCN report noted that their extensive burrow systems posed a potential danger to Hooker’s sea lions because pups could become trapped and potentially suffocate inside them.

By 1991, estimates suggested that thousands of rabbits were still living on Enderby Island. A subsequent review of the eradication programme put the population at approximately 5,000 to 6,000 animals at the time. The Department of Conservation had already conducted poison-bait trials in 1991 and 1992 before moving ahead with the eradication programme.

50 rabbits were removed before the eradication

The conservation authorities nevertheless took steps to ensure that the distinctive rabbit population would not disappear entirely. Before the eradication operation, the Department of Conservation worked with the Rare Breeds Conservation Society of New Zealand to capture a representative group of animals.

In September 1992, 50 Enderby rabbits were captured and transferred to the mainland. Forty-nine survived the transfer and subsequently became the foundation of a managed breeding population.

The following year, the remaining rabbits on Enderby Island were targeted for eradication as part of the wider programme to remove introduced mammals and restore the Auckland Islands ecosystem. Government records indicate that the operation ran from February to May 1993. Monitoring completed by February 1994 found no evidence of rabbits remaining on Enderby Island or nearby Rose Island.

The rabbits survived, but not on Enderby Island

The decision to remove the rabbits from their original island habitat did not result in the complete disappearance of the population. Instead, the 49 surviving animals provided the foundation for breeding programmes designed to preserve the Enderby rabbit lineage on the mainland.

The New Zealand Journal of Ecology has noted that breeding groups representing the Enderby rabbits continue to be maintained in New Zealand. However, the population has remained below the level considered necessary to provide a strong guarantee of long-term survival.

Today, the Enderby rabbits no longer live in the cold and isolated environment that shaped them for more than a century. Their survival instead depends on managed breeding programmes that have maintained the population for more than three decades.

The story of the Enderby rabbits illustrates an unusual conservation dilemma: an animal can be both an introduced species that threatens an ecosystem and a genetically distinctive population worth preserving. In this case, the solution was to restore the island while removing a carefully selected group of rabbits first, allowing the unusual population created by 127 years of isolation to survive elsewhere.