Ecological barriers mediate spatiotemporal shifts of bird communities at a continental scale.

Species' range shifts and local extinctions caused by climate change lead to community composition changes. At large spatial scales, ecological barriers, such as biome boundaries, coastlines, and elevation, can influence a community's ability to shift in response to climate change. Yet, ecological barriers are rarely considered in climate change studies, potentially hindering predictions of biodiversity shifts. We used data from two consecutive European breeding bird atlases to calculate the geographic distance and direction between communities in the 1980s and their compositional best match in the 2010s and modeled their response to barriers. The ecological barriers affected both the distance and direction of bird community composition shifts, with coastlines and elevation having the strongest influence. Our results underscore the relevance of combining ecological barriers and community shift projections for identifying the forces hindering community adjustments under global change. Notably, due to (macro)ecological barriers, communities are not able to track their climatic niches, which may lead to drastic changes, and potential losses, in community compositions in the future.

Setting priorities for climate change adaptation of Critical Sites in the Africa-Eurasian waterbird flyways.

Despite their importance for biodiversity and ecosystem services, wetlands are among the most threatened ecosystems globally. The conservation of many migratory waterbirds depends on the conservation of a network of key sites along their flyways. However, the suitability of these sites is changing under climate change, and it is important that management of individual sites in the network adapts to these changes. Using bioclimatic models that also account for changes in inundation, we found that projected climate change will reduce habitat suitability for waterbirds at 57.5% of existing Critical Sites within Africa-Eurasia, varying from 20.1% in Eastern Europe to 87.0% in Africa. African and Middle East sites are particularly threatened, comprising 71 of the 100 most vulnerable sites. By highlighting priority sites for conservation and classifying Critical Sites into Climate Change Adaptation Strategy (CCAS) classes, our results can be used to support the climate change adaptation of both individual sites and the entire site network.

Ru-Birds.RU, bird observations from Russia and neighbouring regions: an occurrence dataset.

BACKGROUND: The dataset covers bird observation occurrences in Russia and neighbouring regions (ex-USSR countries and some other countries of Eastern and Western Europe) from 2001-2021. It is based on the internet platform "Online bird observation diaries" (ru-birds.ru), which allows professional ornithologists and amateur bird lovers to exchange their results and to jointly build a common collection of data. The taxonomic backbone of the occurrence dataset follows the standardised GBIF checklist dataset to ensure correct cross-linking of the names.Currently, the database contains 541,900 records of occurrences of 713 bird species, which makes it the largest dataset on birds of Russia and neighbouring regions published in GBIF. NEW INFORMATION: The occurrence dataset contributes to filling gaps in the bird distribution in Russia and Eastern Europe. It can be used for a deeper look at their populations, phenology and migrations over this area. The availability of special tools for verification of the entered information makes the database a valuable tool for analysing occurrences of non-native species, studying vagrancy, immigration, invasions and range dynamics.The dataset is regularly updated. Over the 11 months of 2021, it has increased by 98,165 occurrences.