SYDNEY, Aug. 12 (Xinhua/APP): Climate change-driven heat extremes have wiped out 25-38 percent of tropical bird populations since 1950, according to a study involving Australian scientists.
The study found that while shifts in average temperature and rainfall have some influence, the biggest climate threat to birds, particularly in tropical regions, comes from exposure to extreme heat, according to an analysis released Tuesday on the University of Queensland website.
Australian and European researchers analyzed over 3,000 bird populations from 1950-2020, using weather data to separate climate impacts from human pressures such as habitat loss, in a dataset of 90,000 observations from all continents, it said.
The research, published in Nature Ecology & Evolution, confirmed the work of other climate scientists showing extreme heat events have increased dramatically over the past 70 years, especially near the equator.
Birds in tropical regions are now experiencing dangerously hot days about ten times more often than they did in the past, researchers have found.
Surviving birds may suffer lasting damage, including organ failure and reduced breeding success, as extreme heat lowers body condition, limits foraging, stresses eggs and chicks, and can cause dehydration or nest abandonment, the study showed.
Researchers warned that even remote, protected tropical forests untouched by humans are seeing heat-driven bird declines, with climate impacts outweighing direct human pressures.
Given that nearly half of all bird species are found in tropical regions, the findings signal a major threat to global biodiversity and urge urgent emission cuts and habitat protection to conserve species.