Testing the cameras and artificial shelters
The camera setup and artificial shelters were tested in the Paluma Range (north-east Queensland, Australia), where a small (3.5 cm body length) microhylid frog (Robust Whistling Frog Austrochaperina robusta ) occurs at high abundance. This species is restricted to mid-elevation and upland rainforest, living among the leaf-litter and under logs and rocks (Hoskin & Hero, 2008). It is extremely cryptic, other than the loud whistling calls of males calling after rain. Austrochaperina robusta is a terrestrial breeding frog, with direct development (tadpoles develop within the eggs), and the small clutch is laid in leaf-litter and under logs and rocks and is attended by an adult frog (Hoskin, 2004). Details of breeding biology, including the role of the adult in caring for the eggs and metamorphs, as well as their year around microhabitat use are unknown due to the small size and cryptic lifestyle.
Thirty artificial concrete and 30 wooden shelters were placed in a known high-density A. robusta area between November 2022–January 2023. To test the most risk-prone parts, switching out batteries and USB drive in the field, we used 30 mAh 12V batteries that can run up to 5 days. Cameras were deployed 14 times during the subsequent breeding season (21 November–23 February), with a minimum deployment of a camera being 3 days and a maximum deployment being 30 days at a shelter. During this period, the batteries and USB drives of the cameras were changed every 3–5 days. This involved a total of 62 battery and USB changes.