Climate Change and Birds: A Critical Review of Evolutionary, Behavioural, and Reproductive Responses

Climate change is now the major driver of biodiversity loss and its effects on species distribution, physiology, and ecology are having a profound effect on the way species are managed. Birds, being sensitive to environmental changes, are therefore good indicators of climate change-induced ecological change. This research reviews the current evidence on the impact of climate change on birds, focusing on their evolution, their behaviour - foraging and migration, and their reproductive success. The increasing temperatures and altered precipitation have disrupted avian phenology and have caused the birds to experience a mismatch between their food availability and the most important events in their life history such as breeding and migration. Climate-driven changes in breeding timing and migration times have negatively impacted reproductive and survival rates in many species. New evidence suggests that micro-evolutionary responses such as the reduction of body size associated with warming could affect fitness across migration routes. Despite the increasing evidence for phenotypic plasticity, there is little evidence that evolutionary adaptation will speed up with climate change. The cumulative impact of climate change and ecological change, habitat changes, and climatic stressors have serious consequences for avian lives worldwide. This review highlights some important research gaps and underscores the need for interdisciplinary and multi-scale approaches to understand and respond to climate change impacts on avian biodiversity.