A geographical assessment of Chariganga and Arpara Beel (wetlands) of Nadia, West Bengal as a habitat of wetland birds

The present study attempts to assess the impact of human intervention on the population, distribution, and habitat perspectives of the water birds found in and around Chariganga and Arpara ‘Beel’ wetlands, leftover channels of the River Bhagirathi. The point count method was adopted during field surveys conducted from April 2019 to March 2020. These wetlands are the natural habitats for 37 species of wetland birds belonging to 18 families and 11 orders, of which 26 species are residents, three are summer migrants, and eight are winter immigrants. The wetlands also harbour 10 bird species whose population is globally declining over the last few decades. Relative Diversity index unveils that among waterfowls Ardeidae is the dominant family. Species richness reaches its peak in winter, and is least during the monsoon. Empirical observation documented one Vulnerable (Greater Adjutant) and one Near Threatened (Black-Headed Ibis) species residing on the banks and adjoining paddy fields. Indiscriminate extraction of wetland products by local people, along with agricultural expansion towards the waterfront of the wetlands, has deteriorated the health of those wetlands and threatened the existence of waterbirds, especially shorebirds. Populations of 22 species living in water edge areas has changed conspicuously owing to cultural and economic activities of neighboring human groups. We suggest improving the ecological balance of the wetlands and restraining further degradation through proper management to preserve avian diversity.