Impact of deer on Secretary Island, Fiordland, New Zealand.

The first deer to invade an area of forest on Secretary Island show an almost exclusive preference for bark of Pseudopanax colensoi var. ternatum. Young shoots of P. linearis and juvenile P. crassifolium are also sought. Intensive browsing is begun in areas of Asplenium bulbiferum and continued where Polystichum vestitum and bushes of Coprosma spp. are plentiful. The foregoing are the main species being killed by deer but others are being taken in increasing quantity. Difficult access has made the island a mosaic of undamaged, selectively browsed and intensively browsed vegetation. The prospects of eliminating deer by poisoning are probably best while P. colensoi bark is available for bait.