Assessment of technological developments for camera‐traps: a wireless transmission system and solar panels

Camera‐trapping is considered a cost‐efficient method to monitor wildlife, but relevant performance constraints remain. We assessed performance and cost‐benefit for 2 recent technological innovations: (i) a wireless transmission system where cameras communicate in a network, and (ii) using solar panels as a camera's sole power supply. The maximum distance between cameras that ensured wireless connection varied between 2 km in open habitats and 335 m in forest habitats with dense tree cover. The cost of using the wireless transmission system was lower for surveys run for >45 days and for >15 sampling units (i.e., camera‐trap sites). For surveys longer than 15 days, using the wireless transmission system required, on average, 8 fewer days of fieldwork. We measured the performance of the solar panels in terms of capture probability, and the solar‐powered cameras (β = −0.015 ± 0.01 in the log scale) outperformed battery‐powered cameras (β = −0.103 ± 0.005) as capture rate decreased more slowly, particularly for nighttime events (difference in capture probability of the solar‐powered relative to the battery‐powered cameras at night, β = 0.09 ± 0.01). We consider that, although camera‐traps with wireless transmission can provide a return on investment for a wide range of survey designs, the constraints on maximum distance for transmission are a limitation. Despite the higher cost, we recommend solar‐powered camera‐traps as they had improved performance with a higher proportion of species events captured than by battery‐powered cameras.