Optimizing the timing of anuran calling surveys in New Jersey.

摘要

Scientists are concerned about amphibians due to their drastic declines in recent decades. It is therefore important to monitor the status of their populations. The North American Amphibian Monitoring Program designates three time periods during the spring and summer in which to conduct roadside call count surveys. Often, conservation organizations must prioritize their resources, and may therefore focus on a few target species, instead of overall diversity. Therefore, it is necessary to know which period will provide the highest likelihood of detecting the target species, so that resources can be allocated most effectively. To better understand the influence of seasonality on anuran call detection, I examined four years of anuran survey data collected from the Edwin B. Forsythe National Wildlife Refuge in Oceanville, NJ. Three out of nine detected species were unevenly distributed across periods: Northern Spring Peeper (Pseudacris crucifer), Fowler's Toad ( Anaxyrus fowleri), and Green Frog (Rana clamitans). There was no significant difference between the average probability of occurrence in each of the three periods. However, five of nine species had their highest probability of occurrence in period three. If a refuge only has the resources to sample during one period, period three is the optimal choice.