Invasive Snake Activity Before and After Automated Aerial Baiting

作者：Shane R. Siers, Aaron B. Shiels, Patrick D. Barnhart · 发表于：Journal of Wildlife Management · 年份：2019 · DOI：10.1002/jwmg.21794 · 被引用次数：20 · 研究领域：Wildlife Ecology and Conservation、Amphibian and Reptile Biology、Animal Ecology and Behavior Studies

ABSTRACT Aerially delivered toxic baits have proven effective for landscape‐level control of numerous invasive vertebrate populations with major benefits for conservation and ecosystem function, but this technique has not been broadly adapted for control of invasive reptiles. Nonnative brown treesnakes (Boiga irregularis) on the Pacific island of Guam have caused severe ecological and economic damage and pose an invasion risk on other islands, making them a high‐profile candidate for application of aerial baiting methods. Although terrestrial applications of traps, toxicants, and hand‐removal are standard brown treesnake management practices, these methods are not cost‐effective for control in the island's large tracts of remote, rugged forest. In 2016, the first major in situ evaluation of a helicopter‐borne automated aerial bait delivery system applied snake‐targeted toxic baits at an effective rate of approximately 120 baits/ha over a 110‐ha forested test plot on Guam. We evaluated the extent and duration of the suppressive effect of this toxic bait application on brown treesnakes by measuring nontoxic bait take rates as a proxy index of relative snake abundance before and after toxic bait application in a treatment plot and surrounding reference area. We placed 4,420 nontoxic baits in random transects at georeferenced locations, from 1 month before until nearly 12 months after toxic bait application, allowing temporal analysis of the suppressive effect and spatial analysi...