No abstract

Basic biological information is critical to evaluating conservation requirements for native taxa, but is lacking for many cryptic New Zealand lizard species. Southern forest geckos (Mokopirirakau 'Southern Forest') are known only from anecdotes, museum specimens and discoveries of an individual at each of three sites during recent surveys in the Catlins. We used systematic searching, photo identification and radio telemetry at one of these sites (Tahakopa Valley) to investigate habitat use of southern forest geckos. Forty-five hours of searching in 2010Á2011 yielded 28 sightings of 17 individuals including four juveniles (indicating that a breeding population exists). Most geckos were found by searching a boulder used as a diurnal retreat site or in mānuka (Leptospermum scoparium). Two geckos were radio-tracked; both remained within 5 m of capture and exhibited primarily nocturnal behaviour. We recommend further survey work to identify populations and monitoring to evaluate the need for conservation intervention.

Artificial retreats are increasingly being used as a tool for monitoring lizard populations in New Zealand. However, relationships between placement of retreats and skink sightings are not well understood. We investigated how microhabitat around and under artificial retreats influences sightings of common skinks (Oligosoma polychroma) in a grassland habitat in Fiordland. Our dataset comprised 2356 skink sightings from 4100 checks of artificial retreats. Mean vegetation height 0.5 m from retreats was positively correlated with skink sightings, but we did not detect relationships between other microhabitat variables and skink counts. Greater vegetation height may provide enhanced habitat complexity, thus supporting a richer faunal community and higher skink density. Alternatively, skink basking opportunities may be more limited under taller vegetation, making nearby artificial retreats more attractive for their thermal properties. We highlight the importance of considering microhabitat when placing artificial retreats to maximise detections of lizards.