Priority ranking for the conservation of all European bryophyte species

Abstract

Biological diversity declines rapidly and resources for conservation actions to halt the loss are limited. It requires setting appropriate conservation priorities. We present an efficient and reproducible approach to identify European bryophytes species that warrant highest conservation attention. We used two independent criteria to define conservation priorities: i) Red List status in Europe; ii) European population size relative to the global population or global rarity, respectively, by combining the best available information with expert judgment. We assigned a quantitative score for both criteria separately to each of the 553 threatened (i.e., Critically Endangered, Endangered, Vulnerable) and Near Threatened species and calculated their sum as the “Priority Score for conservation”. Applying this global perspective, the conservation priorities presented here differ from a prioritisation solely based on regional Red List status. We used distinct thresholds to the Priority Scores, which resulted in 135 (24 %) species of high, 126 (23 %) of medium, and 292 (53 %) of low priority for conservation. We provide occurrence data for each species, and for additional European endemics, together with conservation priority scores for all European countries or territories, making the priority scheme readily applicable for national conservation decisions. Areas with oceanic climates, especially Macaronesia, and mountainous regions harbour many species of conservation concern. We recommend a process how to apply the Priority Scores in the scope of national legislation, policies and expertise. Our method will assist national agencies and conservationists to direct resources to conservation actions for bryophytes whose persistence in Europe is critical from a global viewpoint.