Defining conservation priorities for freshwater fishes according to taxonomic, functional, and phylogenetic diversity

Abstract

To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential trade‐offs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity; contemporary threats to biodiversity (including interactions with nonnative species); and future climate change and human population growth. There was 75% congruence between areas of highest conservation priority for different aspects of biodiversity, suggesting that conservation efforts can concurrently achieve strong complementarity among all types of diversity. However, sizable fractions of the landscape were incongruent across conservation priorities for different diversity scenarios, underscoring the importance of considering multiple dimensions of biodiversity and highlighting catchments that contribute disproportionately to taxonomic, functional, and phylogenetic diversity in the region. Regions of projected human population growth were not concordant with conservation priorities; however, higher human population abundance will likely have indirect effects on native biodiversity by increasing demand for water. This will come in direct conflict with projected reductions in precipitation and warmer temperatures, which have substantial overlap with regions of high contemporary diversity. Native and endemic fishes in arid ecosystems are critically endangered by both current and future threats, but our results highlight the use of systematic conservation planning for the optimal allocation of limited resources that incorporates multiple and complementary conservation values describing taxonomic, functional, and phylogenetic diversity.

Global priorities for conservation across multiple dimensions of mammalian diversity

“…1. of biodiversity has been observed globally for birds (26), freshwater fishes (22), and mammals (15). Such lack of congruence triggers a conservation conflict, because conservation strategies based only on taxonomic diversity do not include important phylogenetic and functional hotspots (15,26).…”

“…We found that removing traits that had high proportions of missing data before imputations did not change our main results. To represent the trait dimension in the prioritization analyses, we followed the framework of Strecker et al (22), using a grid cells × traits matrix. To create this matrix, all trait variables were converted into binary format.…”

“…Complementarity-based selection of priority areas allows the representation of all biological features without much duplication of sites with similar species, resulting in a more costeffective conservation solution (12). For example, Strecker et al (22) performed the first complementarity-based prioritization, considering separately taxonomic, phylogenetic, and trait diversity in freshwater fish, highlighting the use of this approach for the optimal allocation of limited conservation resources that incorporates multiple dimensions of biodiversity.…”

“…There is clearly a need for spatial conservation priorities that account for multiple dimensions of biological diversity, including taxonomy, phylogeny, and traits (15,21,22). However, the relationships among these dimensions across the globe are poorly understood and vary depending on the metric used and the scale of the analysis (15,23).…”

Conceptual and empirical advances in Neotropical biodiversity research

“…As result, researchers tend to focus on different aspects of biodiversity such as 83 taxonomic, phylogenetic, and functional diversity (Swenson, 2011). Each of these aspects of biodiversity 84 may vary differently among regions and taxa, and each must therefore be assessed by independent criteria 85 (Strecker et al, 2011). 86 …”