Phenology and environmental determinants of explosive breeding in gliding treefrogs: diel timing of rainfall matters.

This article focuses on the reproductive phenology and environmental determinants of explosive breeding in the gliding treefrog, *Agalychnis spurrelli*, on Costa Rica’s Osa Peninsula. Through 418 days of monitoring across three breeding seasons, combining long-term natural history observations, automated acoustic recordings, and boosted regression tree (BRT) analyses, the study found that breeding occurs in short, intense aggregations up to 11 times per year, primarily triggered by heavy rainfall in the preceding 24 to 48 hours, especially during afternoon and evening periods. Additional factors influencing breeding and calling activity include day-of-year, days since last breeding, humidity, and lunar phase, with breeding concentrated early in the rainy season and calling more frequent during darker lunar phases. This research provides the first detailed quantitative analysis of explosive breeding phenology in *A. spurrelli* and demonstrates the effectiveness of integrating automated data collection with machine-learning methods to analyze complex ecological patterns in tropical amphibians.