In a recent study, researchers found that a significant portion of the world’s bird species do not thrive in human-dominated environments and are more likely to have declining populations. Specifically, 78% of bird species are unable to breed successfully in heavily modified landscapes. This poses a threat to biodiversity as these species are also more likely to be at risk of extinction. Currently, 14% of the world’s 11,000 bird species are threatened with extinction, highlighting the urgent need for conservation efforts to protect these vulnerable populations.
The study assessed the populations of bird species across a range of habitats, from pristine environments to those heavily impacted by human activities. It determined that threatened species and those with declining populations are less tolerant of breeding in human-dominated habitats. For example, the Fern Wren, a species found only in tropical forests of northeastern Australia, is endangered, has a declining population, and exhibits a very low tolerance to human pressure. This emphasizes the importance of preserving and protecting natural habitats for these sensitive species.
While some bird species struggle to adapt to human-dominated environments, others demonstrate a high level of tolerance and can thrive even in urban areas. The Common Swift, for example, is known to breed in cities across the world, showcasing their ability to coexist with human activities. Understanding the differences in tolerance levels among bird species can help inform conservation strategies and target efforts towards protecting the most vulnerable populations that require specific habitat conditions to thrive.
In line with the UN’s Kunming-Montreal Global Biodiversity Framework, conservation goals have been set to protect 30% of the Earth’s land, but much of this percentage may not consist of pristine habitats. Identifying and prioritizing species that are particularly sensitive to human activity, such as the Great Snipe in Europe, the Nkulengu Rail in Africa, and the Hume’s Lark in Asia, can help focus conservation actions on protecting or restoring habitats for these species. By targeting efforts towards the species and locations that need it most, conservationists can maximize the impact of their interventions.
Europe and North America were found to have higher proportions of human-tolerant bird species compared to Latin America and Africa. This difference may be attributed to the historical impacts of human activities on the environment in these regions, leading to the disappearance of sensitive species and allowing others to adapt over time. Understanding these historical patterns can provide insights into how bird species have responded to changing landscapes and human pressures over time.
Overall, the study quantified the tolerance of 6,000 bird species to breeding in human-dominated environments using data from citizen science observations and the Human Footprint Index, which measures the combined pressures of built environments, human population density, night-time lights, agriculture, and roads. The findings offer valuable insights into how different bird species interact with human activities and highlight the importance of targeted conservation efforts to protect vulnerable populations and preserve biodiversity.
