Seasonal Variation of Avifauna in Chintamani Kar Bird Sanctuary, West Bengal, India

Chintamani Kar Bird Sanctuary (CKBS), situated in the peri-urban zone of southern Kolkata, West Bengal, constitutes a critical refuge for avian biodiversity within an increasingly urbanised landscape. Encompassing approximately 17 acres, the sanctuary comprises a heterogeneous mosaic of vegetation types including semi-deciduous tree cover, bamboo stands, fruiting trees, and ephemeral aquatic features. These habitat structures provide essential ecological resources – such as food, nesting substrates, and microclimatic regulation – upporting both resident and migratory avifaunal communities. This study aims to examine the seasonal variation in avian diversity at CKBS, with a focus on how climatic fluctuations and associated habitat dynamics influence species richness, abundance, and community composition. Data were compiled through longitudinal field observations and literature synthesis across three major seasonal phases: pre-monsoon/summer (March – June), monsoon (July – September), and post-monsoon/winter (October – February). Avifaunal richness was observed to peak during the post-monsoon and winter periods, coinciding with the arrival of Palearctic migrants along the Central Asian Flyway. The cooler ambient temperatures, reduced evapotranspiration, and increased trophic resource availability during this period facilitated optimal foraging and roosting conditions. Notably, species adapted to high-humidity environments, including select Ardeidae and Columbidae, remained active. The pre-monsoon period exhibited moderate avian diversity, dominated by resident frugivores and granivores, with breeding activity peaking in synchrony with fruiting phenology of native flora. The findings of this study underscore the role of seasonal climatic variability and habitat heterogeneity in shaping temporal avifaunal dynamics within urban forest fragments. CKBS, despite its limited spatial extent, maintains high ornithological value and warrants continuous monitoring and conservation intervention to mitigate the impacts of anthropogenic encroachment and environmental change.