Filling gaps in a large reserve network to address freshwater conservation needs

Abstract

Freshwater ecosystems and biodiversity are among the most threatened at global scale, but efforts for their conservation have been mostly peripheral to terrestrial conservation. For example, Natura 2000, the world's largest network of protected areas, fails to cover adequately the distribution of rare and endangered aquatic species, and lacks of appropriate spatial design to make conservation for freshwater biodiversity effective. Here, we develop a framework to identify a complementary set of priority areas and enhance the conservation opportunities of Natura 2000 for freshwater biodiversity, using the Iberian Peninsula as a case study. We use a systematic planning approach to identify a minimum set of additional areas that would help i) adequately represent all freshwater fish, amphibians and aquatic reptiles at three different target levels, ii) account for key ecological processes derived from riverscape connectivity, and iii) minimize the impact of threats, both within protected areas and propagated from upstream unprotected areas. Addressing all these goals would need an increase in area between 7 and 46%, depending on the conservation target used and strength of connectivity required. These new priority areas correspond to subcatchments inhabited by endangered and range restricted species, as well as additional subcatchments required to improve connectivity among existing protected areas and to increase protection against upstream threats. Our study should help guide future revisions of the design of Natura 2000, while providing a framework to address deficiencies in reserve networks for adequately protecting freshwater biodiversity elsewhere.

Gaps in ecological research on the world's largest internationally coordinated network of protected areas: A review of Natura 2000

“…Using fish to explicitly study connectivity of freshwater habitats is particularly relevant for the functioning of N2k as a habitat network (e.g. Hermoso et al, 2015).…”

Whole‐landscape modelling of compositional turnover in aquatic invertebrates informs conservation gap analysis: An example from south‐western Australia

“…rare species habitat) and often fail to address key ecological processes, such as whole catchment integration and connectivity (Darwall et al., ; Dudgeon et al., ; Linke et al., ). There is a need to assess how well represented freshwater systems actually are within terrestrial protected areas (Abell et al., ; Hermoso, Filipe, Segurado, & Beja, ; Kingsford & Nevill, ; The Nature Conservancy, ; Thieme, Rudulph, Higgins, & Takats, ).…”

Catchment zoning to unlock freshwater conservation opportunities in the Iberian Peninsula

“…In scenario 1, we identified priority areas for conservation using Marxan as demonstrated in previous studies (e.g. Hermoso et al ., , ). We locked in all subcatchments adequately covered by Natura 2000 (> 75% of subcatchment covered under Natura 2000), so our objective was to find a minimum set of areas to fill the representation gaps for freshwater biodiversity in Natura 2000 reported in Hermoso et al .…”