Improved detection of arboreal geckos using tree‐mounted Onduline artificial refuges

ABSTRACT The cryptic nature and low densities of many reptile populations world‐wide presents significant challenges for their detection, monitoring and conservation management. Artificial refuges (also known as artificial cover objects and artificial retreats) are a standard method used to sample terrestrial lizards throughout New Zealand. Despite the development of multiple refuge designs for arboreal species, encounter rates are typically low in areas with mammalian predators, particularly for geckos living in tall forest. Here, we compared the effectiveness of novel tree‐mounted Onduline refuges with conventional refuge designs for detecting Waitaha gecko ( Woodworthia cf . brunnea ) and broad‐cheeked gecko ( Mokopirirakau ‘Okarito’) in tall podocarp forest in Riccarton Bush, Christchurch, and Westland Tai Poutini National Park, respectively. At both sites, the largest Onduline refuge design was the most effective for detecting geckos, yielding 69% of Waitaha gecko encounters over 25 sampling occasions between May 2020 and March 2023, and 62% of broad‐cheeked gecko encounters over 10 occasions between December 2021 and December 2023. Closed‐cell foam covers were the least effective design, yielding 6% and 0% of Waitaha and broad‐cheeked gecko encounters, respectively. Additional research is needed to define optimal conditions for arboreal gecko occupancy and sampling a greater range of species with tree‐mounted Onduline refuges.