Vegetation and flora of Sail Rock, Hen and Chickens Islands

摘要

Sail Rock appears to be the least modified of the small islands so far described from the Hauraki Gulf, northern New Zealand. The four communities mapped can be correlated with sites of differing stability; a vegetation ofDisphyma australeandMuehlenbeckia complexaon cliffs,Coprosma repensscrub on unstable slopes of fine talus,Corynocarpus laevigatusforest on an unstable slope of boulders, andParatrophis banksii-Melicope ternataforest on a semistable talus slope. The composition of the island's vegetation, compared to other islands, can be related to lack of disturbance by fire and the absence on Sail Rock of the kiore or Polynesian rat (Rattus exulans). Although small, the island can be used as part of a discontinuous control area for studying the effects of this rat on the flora, fauna, and structure of New Zealand coastal communities.