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Documentation of biodiversity and its geographical distribution is necessary to understand the processes and drivers of evolutionary diversification as well as to guide conservation and management initiatives. Among the most emblematic patterns of biodiversity in the world’s oceans is the Coral Triangle (Indo-Australian Archipelago), widely recognized to be the center of species richness for a variety of marine life forms. The distribution of biodiversity remains incompletely documented, however, for a majority of reef-associated invertebrate taxa, including the zooxanthellate soft corals (Octocorallia) that dominate hard substrate on many Indo-Pacific reefs. We used a genetic approach to document the diversity of Indo-Pacific soft corals, sequencing two single-locus barcoding markers for > 4400 soft coral specimens and assigning individuals to molecular operational taxonomic units as proxies of species. We document two centers of species richness for zooxanthellate soft corals, one in the Indo-Australian Archipelago and a second, equally diverse center in the Western Indian Ocean. Centers of endemicity for soft corals are coincident with these centers of species richness, although the peripheral Red Sea and Hawaii also support high proportions of endemic taxa. The patterns documented here suggest that biogeographic distributions of soft coral families may be driven in part by larval dispersal potential: taxa with benthic larvae are absent from most oceanic islands of the central Pacific and are represented by higher proportions of endemic taxa in other geographic regions. Our findings demonstrate the distinct biogeographic patterns among reef taxa and underscore the need to document and analyze species distributions of more reef-associated invertebrate groups to derive a complete picture of reef biogeography.
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Social–environmental drivers inform strategic management of coral reefs in the Anthropocene
Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages—the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014–2017 global coral bleach- ing event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.
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- Award ID(s):
- 1737071
- PAR ID:
- 10148483
- Date Published:
- Journal Name:
- Nature ecology evolution
- Volume:
- 3
- Issue:
- September
- ISSN:
- 2397-334X
- Page Range / eLocation ID:
- 1341–1350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41559-019-0953-8
