Potential impacts of climatic change upon geographical distributions of birds

摘要: Potential climatic changes of the near future have important characteristics that differentiate them from largest magnitude and most rapid Quaternary. These potential are thus a cause for considerable concern in terms their possible impacts upon biodiversity. Birds, common with other terrestrial organisms, expected to exhibit one two general responses change: they may adapt changed conditions without shifting location, or show spatial response, adjusting geographical distribution response changing climate. The Quaternary geological record provides examples organisms responded fluctuations period each these ways, but also indicates not alternative components same overall predominantly response. Species unable achieve sufficient by either both mechanisms will be at risk extinction; documents such extinctions. Relationships between distributions birds present climate been modelled species breeding Europe Africa. resulting models very high goodness-of-fit provide basis assessing anthropogenic avian richness continents. Simulations made range circulation model projections late 21st century lead conclusion likely substantial. boundaries many species’ shifted  1000 km. There is decline richness, mean extent decrease. restricted specialized particular biomes suffer greatest impacts. Migrant especially large as change alters wintering areas, well critical stopover sites, potentially increases distances must migrate seasonally. Without implementation new conservation measures, severe exacerbated land-use associated habitat fragmentation. Unless strenuous efforts address root causes change, much current effort conserve biodiversity vain.