Toward Better Monitoring of Cryptic Lizards: Catch Rate Predictors and Natural History of the Elusive Northern Striped Gecko Toropuku inexpectatus

The nocturnal and arboreal northern striped gecko ( Toropuku inexpectatus ) is one of Aotearoa New Zealand's most elusive and least‐detected lizards, classified as Threatened – Nationally Vulnerable. Limited knowledge of its biology, ecology and distribution poses challenges for monitoring and conservation. To improve understanding of this species and how environmental conditions may influence detection rates, we collected morphological and environmental data during 80 nocturnal surveys conducted between 2016 and 2025 in the Mahakirau Forest Sanctuary, Coromandel Peninsula, North Island, New Zealand. We recorded observations on morphology, habitat preference, birthing season and population demographics and then evaluated the effects of season, temperature, relative humidity, wind speed and moon fullness on gecko catch rates. Maximum snout–vent length (SVL) of processed geckos was 95 mm for females and 89 mm for males, with significant sexual size dimorphism. The smallest individuals (minimum 37 mm SVL) were captured in late autumn to early winter, indicating likely timing of parturition. We found a significant negative effect of moon fullness on gecko catch rates, with fewer geckos captured during brighter nights. The effect of temperature on catch rate differed among seasons, with a significant negative association in spring and no clear effect in other seasons. These results are consistent with predator‐avoidance behaviour on brighter nights and the influence of thermal environment on reptile activity and detectability. Optimising efficiency and success rates of monitoring programmes for this and other highly elusive species is critical to establishing robust population trend data and informing conservation management.