Introduced mammals and islands: Priorities for conservation and research

[First paragraph...]
With so much of New Zealand's land surface transformed during the past 120 years, many small off-shore and outlying islands are now unique samples of the relatively undisturbed environment. But the very characteristics that have protected and isolated them in nearly primitive condition also make them extremely vulnerable to further disturbance. Many have already been drastically modified by introduced mammals such as goats, pigs, rabbits, cats and rats, or through exploitation by man. On some, these animals were introduced long ago and their populations now approach equilibrium with the modified environment. On others, populations of introduced mammals are declining naturally, often where a dominant and increasing vegetation is making the environment progressively less favourable for them. On a few other islands, especially where introduced animals have only recently become established, the original flora and fauna is being modified rapidly