Natural history of the lizards of the three kings Islands, New Zealand

Abstract

The herpetofauna of the Three Kings Islands comprises one gecko (Hoplodactylus aff. H. pacificus) and four skinks (Cyclodina ornata, Oligosoma fallai, O. smithi, and O. suteri). Great, North East, and South West Islands have all five species, and the other islands and islets each have 2–4 species. Hoplodactylus aff. H. pacificus and O. suteri have the widest distribution (10 islands each) followed by O. fallai on nine islands. The lizard fauna is relatively depauperate, probably because of the islands’ degree and length of isolation. O. fallai, endemic to the Three Kings group, is mostly diurnal but also active at night. Specimens of Hoplodactylus aff. H. pacificus collected from the Three Kings Islands were significantly larger on average (82.1 mm) than specimens of H. pacificus from elsewhere (69.1 mm) and may constitute an endemic subspecies or species. Specimens of O. suteri had a maximum snout‐vent length of 126 mm on the Three Kings group, compared with 108 mm elsewhere. There was no sexual dimorphism in snout‐vent length in Hoplodactylus aff. H. pacificus, O. fallai, and O. suteri. Specimens of O. fallai from forest were significantly larger on average than those from scrub, which were in turn larger than those from coastal sites. In both Hoplodactylus aff. H. pacificus and O. fallai there was evidence that not all mature females bred every year, consistent with a trend towards low annual reproductive rates among New Zealand lizards.