Critical catchments for freshwater biodiversity conservation in Europe: identification, prioritisation and gap analysis

Abstract

Summary The conservation of freshwater ecosystems has lagged behind that of marine and terrestrial ecosystems and often requires the integration of large‐scale approaches and transboundary considerations. This study aims to set the foundations of a spatial conservation strategy by identifying the most important catchments for the conservation of freshwater biodiversity in Europe. Using data on 1296 species of fish, mollusc, odonate and aquatic plant, and the key biodiversity area criteria (species Red List status, range restriction and uniqueness of species assemblages), we identified a network of Critical Catchments for the conservation of freshwater biodiversity. Applying spatial prioritisation, we show how the prioritised network differs from the ideal case of protecting all Critical Catchments and how it changes when protected areas are included, and we also identify gaps between the prioritised network and existing protected areas. Critical Catchments (n = 8423) covered 45% of the area of Europe, with 766 qualifying (‘trigger’) species located primarily in southern Europe. The prioritised network, limited to 17% of the area of Europe, comprised 3492 catchments mostly in southern and eastern Europe and species targets were met for at least 96% of the trigger species. We found the majority of Critical Catchments to be inadequately covered by protected areas. However, our prioritised network presents a possible solution to augment protected areas to meet policy targets while also achieving good species coverage. Policy implications. While Critical Catchments cover almost half of Europe, priority catchments are mostly in southern and eastern Europe where the current level of protection is not sufficient. This study presents a foundation for a Europe‐wide systematic conservation plan to ensure the persistence of freshwater biodiversity. Our study provides a powerful new tool for optimising investment on the conservation of freshwater biodiversity and for meeting targets set forth in international biodiversity policies, conventions and strategies.

High Variability Is a Defining Component of Mediterranean-Climate Rivers and Their Biota

“…Streams and rivers from Mediterranean-climate regions show the same trends evident in the global pattern of freshwater-biodiversity loss [126,127] that present alarming declines over the last decades, especially in mollusk and fish populations [128][129][130][131]. We suspect that the same is true for many macroinvertebrate species but the data on these taxa at the species level is generally lacking.…”

“…The authors assessed the concordance of these catchments with existing protected areas and found that most high-priority catchments were inadequately covered. Likewise, Carrizo et al [131] identified priority catchments for freshwater conservation at the European scale and showed that most were located in Southern Europe and also not fully covered by existing protected areas. This is not surprising considering that the Mediterranean Basin is, among all the Mediterranean-climate regions of the world, the one with the lowest protection level [128].…”

Important Plant Areas: revised selection criteria for a global approach to plant conservation

“…The concept of KBAs has been in use for some time (Eken et al 2004;Langhammer et al 2007), and widely employed in a number of geographical regions (e.g., Eken et al 2004;Gerlach 2008;Kasecker et al 2009;Paese et al 2010;Melovski et al 2012) and ecological zones such as freshwater ecosystems (Holland et al 2012;Carrizo et al 2014). However, a fully standardised methodology for their identification, based on a single set of criteria for all organism groups with strict quantitative thresholds-the KBA Standardhas only recently been launched .…”

Aquatic biodiversity in Europe: a unique dataset on the distribution of Trichoptera species with important implications for conservation

“…for the establishment of IUCN Red Lists of threatened species (Ferrier, 2002;IUCN, 2012) or the identification of critical areas for biodiversity conservation (Carrizo et al, 2017). Furthermore, it also serves as a valuable basis for quality control of species determinations.…”