Marine bivalves are important components of ecosystems and exploited by humans for food across the world, but the intrinsic vulnerability of exploited bivalve species to global changes is poorly known. Here, we expand the list of shallow-marine bivalves known to be exploited worldwide, with 720 exploited bivalve species added beyond the 81 in the United Nations FAO Production Database, and investigate their diversity, distribution and extinction vulnerability using a metric based on ecological traits and evolutionary history. The added species shift the richness hotspot of exploited species from the northeast Atlantic to the west Pacific, with 55% of bivalve families being exploited, concentrated mostly in two major clades but all major body plans. We find that exploited species tend to be larger in size, occur in shallower waters, and have larger geographic and thermal ranges—the last two traits are known to confer extinction-resistance in marine bivalves. However, exploited bivalve species in certain regions such as the tropical east Atlantic and the temperate northeast and southeast Pacific, are among those with high intrinsic vulnerability and are a large fraction of regional faunal diversity. Our results pinpoint regional faunas and specific taxa of likely concern for management and conservation.
Extinction risk in extant marine species integrating palaeontological and biodistributional data.
Extinction risk assessments of marine invertebrate species remain scarce,
which hinders effective management of marine biodiversity in the face of
anthropogenic impacts. To help close this information gap, in this paper
we provide a metric of relative extinction risk that combines palaeontological
data, in the form of extinction rates calculated from the fossil record, with
two known correlates of risk in the modern day: geographical range size
and realized thermal niche.We test the performance of this metric—Palaeontological Extinction Risk In Lineages (PERIL)—using survivorship analyses of Pliocene bivalve faunas from California and New Zealand, and then
use it to identify present-day hotspots of extinction vulnerability for extant
shallow-marine Bivalvia. Areas of the ocean where concentrations of bivalve
species with higher PERIL scores overlap with high levels of climatic or
anthropogenic stressors should be considered of most immediate concern
for both conservation and management.
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- Award ID(s):
- 1633535
- NSF-PAR ID:
- 10077205
- Date Published:
- Journal Name:
- Proceedings - Royal Society. Biological sciences
- Volume:
- B 285
- ISSN:
- 1471-2954
- Page Range / eLocation ID:
- 20181698
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
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Accepted Manuscript1.0
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