Species Drift Without Decline: Avian Responses to Climate and Habitat

Birds are a faunal taxon that is highly sensitive to global climatic changes. Bird migration is one of the major bioindicators of habitat destruction and climate change. This study refers to bird species drift and migratory pattern changes due to habitat destruction and climate variation. The study was conducted at Jigani Lake Anekal Taluk, Bangalore, Karnataka, India (comparative analysis of 45 avian species was performed based on the available e-bird data and personal documentations (2020 to 2024). Out of 175 recorded species, considering the deviations that have occurred from the usual trend followed until 2020. Desertification, a decrease in water-holding capacity, rising temperatures, and altered precipitation patterns have affected migratory timing and vulnerability during long migrations, distribution ranges, egg-laying timing, clutch size, and the mismatch between behavior and the environment, causing a drift in avian species and populations. These changes have not caused a decrease in avian species numbers but have led to considerable species drift. These changes have led to an increased reproductive success in avian species like Pavo cristatus, Vanellinae sp. Etc. Conversely, many species have altered their migratory patterns. Many of the water birds, which were the regular migrants to the lake, have become passage migrants, whereas the migratory birds that prefer dry habitats like Coracias garrulus (European Roller) are observed . Introduction to invasive plantations, pollution, constructions, and other anthropogenic disturbances has caused degradation to the actual ecosystem. This can be considered as an epitome of climate change and ecosystem changes occurring in Bangalore. The paper emphasises the importance of wetland conservation, the need to restore and maintain biodiversity.