Simultaneous 'hotspots' and 'coldspots' of marine biodiversity and implications for global conservation

Abstract

Global and smaller-scale assessments of biodiversity typically use only 'species' measures. Using a broader set of concepts, we show that different biodiversity elements can exhibit contrasting patterns within the same environment. The Arabian Gulf, estuaries and hydrothermal vents are stressful environments having low species richness yet high β(turnover)-diversity, and around vents taxonomic distinctness is also marked. Similarly, in the Atlantic, β-diversity of starfishes declines from the coasts to the deep sea, contrasting with patterns of species richness and taxonomic distinctness. Thus, environments can, unexpectedly, be both 'hotspots' and 'coldspots' of biodiversity. These results have major implications for international conservation programmes which use biodiversity as a major criterion for identifying priority regions. Unpicking and prioritizing biodiversity's different threads will help environmental organisations better define and target hotspot regions. Current applications of complementarity could theoretically be expanded from a regional to a global perspective, to determine areas in which biodiversity representation is maximal but concepts are not applicable to assemblage properties (e.g. taxonomic distinctness).

The Benthic Megafaunal Assemblages of the CCZ (Eastern Pacific) and an Approach to their Management in the Face of Threatened Anthropogenic Impacts

“…However there are two aspects of diversity that traditional diversity indices do not consider: taxonomic diversity-whether the species present are closely or distantly related; and functional diversity-whether the species present perform similar or contrasting functional roles within the ecosystem (Williams et al, 1996;Price, 2002). It has been considered a priority to develop new metrics that are process oriented and that account for ecosystem dynamics across temporal and spatial scales (Steneck, 2001;Price et al, 2007), highlighting so far as possible the importance of key functional groups, ecological roles and species interactions (Hughes et al, 2005).…”

“…These include average taxonomic distinctiveness (which is a measure of the mean taxonomic distance between species within a sample or study area), and variation in taxonomic distinctiveness which is a measure of the variance in taxonomic distance between species; both are relatively insensitive to sample size (Warwick and Clarke, 2001). In addition, complementing the idea of taxonomic distinctiveness, the concept of taxonomic similarity, the mean taxonomic distance between species from different samples or sites, has been introduced, allowing comparison across areas at different scales; this measure is likewise relatively insensitive to sampling intensity (Izsak and Price, 2001;Price, 2002;Price and Izsak, 2005). It is increasingly considered that such taxonomic diversity measures of biodiversity at both within-habitat and within-region scales, including across and between large ocean provinces, are invaluable for comparing and monitoring environments where full species lists are impracticable to attain Clarke, 1995, 2001;Gray, 1997;Price, 1999;Izsak and Price, 2001), and we propose their wider use for future assessing and monitoring in the CCZ.…”

Human Impacts on Marine Biodiversity: Macrobenthos in Bahrain, Arabian Gulf

“…Although macrobenthos in the Arabian Gulf are characterized by high levels of biodiversity, they are distinguished by low species richness due to harsh environmental conditions such as high levels of salinity and temperature (Al-Yamani et al, 2009;Basson et al, 1977;Price, 2002;Sheppard et al, 2010). Additional anthropogenic effects could arguably be critical for biodiversity and abundance of macrobenthos inhabiting the naturally stressed marine 10 km ‫ــــــــــــــ‬ N environment of the Arabian Gulf, which is considered among the highest anthropogenically impacted regions in the world (Halpern et al, 2008).…”

Diverse approaches to questions of Biodiversity: German contributions to studies of Marine Benthos around South America and Antartica

“…Information about environmental conditions is, of course, also necessary, as only comparisons between areas with different ecological conditions will yield results which can be used for reaching conclusions in a broader context. The choice of spatial scale can significantly affect general results and conclusions (Gray 2001, Price 2002. The coverage of as broad a range of scales as possible is therefore recommended, from single point through local and regional to continental diversity, the latter being directly linked to the first question.…”