Use of constructed rock piles by lizards in a grassland habitat in Otago, New Zealand

The main drivers of lizard population declines in Aotearoa New Zealand are habitat loss and introduced predators. Therefore, habitat enhancement could be useful for mitigating declines, but there is little information on how Aotearoa’s lizards respond to these interventions. We examined whether novel habitats created by ten c. 375 m3 constructed rock piles would be used by McCann’s skinks (Oligosoma maccani), southern grass skinks (O. aff. polychroma Clade 5), and kōrero geckos (Woodworthia “Otago/Southland large”). The rock piles and their immediate edges were surveyed 22 times between four months and 2.4 years post-construction, resulting in 228 sightings of McCann’s skinks on all ten piles, 20 sightings of southern grass skinks on six piles, and two sightings of kōrero geckos on two piles. Estimated abundance of McCann’s skinks increased over time, and neonates were observed. These observations indicate that rock pile construction could create habitats for McCann’s skinks, but further inference is limited. We recommend that future mitigation programs quantify how habitat construction affects lizard populations and suggest methods for achieving this.