Bird communities will be disrupted in protected areas and Important Bird and Biodiversity Areas
The bird species of conservation concern for which IBAs have been identified may not remain in these sites as climate changes, or other species could colonise as climate becomes suitable. Such turnover will be high in the majority of IBAs and Protected Areas. Although these site networks as a whole will provide suitable conditions for nearly all species of conservation interest, disruption of bird communities may affect ecosystem functioning and the benefits to people.
Many IBAs are projected to experience high turnover in bird species of conservation concern
Turnover in the bird species occurring in IBAs in sub-Saharan Africa is projected to be high under future climatic scenarios. That said, 88-92% of species of conservation concern are projected to have suitable climatic conditions remaining by 2085 in at least some sites where they currently occur. This demonstrates that existing IBAs will remain important for conservation under climate change.
The degree of disruption to bird communities in IBAs will increase through the 21st century
Bird community composition in two Asian IBA networks is projected to change dramatically under future climatic scenarios, with an increase in species turnover from 19% in 2025 to 43% by 2085. Models suggest that 45% of species will have less suitable climate in these sites by 2085, highlighting the level of disruption in communities projected to occur.
Bird communities in California will undergo substantial disruption under climate change
Community disruption may lead to completely novel avian assemblages (i.e. combinations of bird species that do not occur together anywhere at present) across 10-57% of California’s land area by 2070. Even in areas retaining species currently present, turnover rates are expected to be high, which could mean a range of new species interactions.
Widespread and substantial shifts are projected for Colombian bird communities
Bird community structure is projected to change dramatically in Colombia, with consequences for species interactions and ecosystem function. Average species richness is expected to decline up to 84% in some regions, with the similarity of current richness and future richness projected to be as low as 30%. Such widespread and substantial shifts in bird communities will likely occur both within and beyond protected areas.