Complete record of oriental rat snake preying on eggs of ring-necked pheasant in a photovoltaic system in Taiwan

Snake predation on bird nests is well-documented globally, yet complete behavioral observations of egg predation are poorly represented in literature. Here, we report repeated egg predation by Ptyas mucosa on a Phasianus colchicus formosanus nest documented via camera trap within a ground-mounted photovoltaic (PV) solar facility from May 9 to June 20, 2025. Predatory visits to the nine-egg nest occurred on three occasions, resulting in the consumption of five eggs, while the remaining four hatched successfully. We quantified snake–bird interactions using a modified parental response scoring system to evaluate defensive behavior during the encounters. Our observations revealed that the female parent maintained active nest defense throughout different time periods, with the intensity of parental responses appearing most pronounced during events where egg predation was actively occurring. All predation events occurred during daytime, consistent with the diurnal habits of Pt. mucosa. This study provides the first documented behavioral record of Pt. mucosa predating Ph. c. formosanus eggs in Taiwan, and highlights the complex ecological dynamics of ground-nesting birds within PV solar facilities. Our findings underscore the need for further research on nest predation risk in renewable energy landscapes to inform conservation strategies for vulnerable ground-nesting species.