Sharks

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Dulvy, N. & Baum, J. You can swim but you can't hide: the global status and conservation of oceanic pelagic sharks a
Sharks

(Chondrichthyes)

Conservation Profile Synopsis Status of Shark Populations

State of the Selachii Superorder

IUCN Red List Total Species

CR EN

VU NT LC

DD

465

11 15

48 67 115 209

CR, Critically Endangered; EN, Endangered; VU, Vulnerable; NT, Near Threatened; LC, Least Concern; DD, Data Deficient.

CITES: Appendix II: 8 species US ESA: Sphyrna lewini Endangered/ threatened USA species of concern: Carcharhinus obscurus, Lamna nasus, Carcharias taurus.

AZA Subpopulation Marine Fishes Taxon Advisory Group Chair

Beth Firchau

Sharks (Superorder Selachii, 10 orders) play a vital role in top-down 1 maintenance of ocean ecosystems around the world . A global assessment of species diversity and abundance has demonstrated that areas with the highest number of data deficient species are located in the Caribbean Sea and Western Central Atlantic Ocean, Eastern Central Atlantic Ocean, Southwest Indian 2 Ocean, and the China seas . Actual landings information reported to the Food and Agriculture Organization of the United Nations (FAO) may be inaccurate since many catches are unregulated, misidentified, unreported, illegal, or discarded, resulting in 2 inadequate species-specific information . Nevertheless, reported global shark catches reveal a rough estimate of catch trends. Shark catches peaked in 2000 at 888,000 tons, which is nearly triple the amount reported in 1950. Since 2000, 2 shark catches have decreased by approximately 15% (756,000 tons in 2012) . It remains unknown as to whether the decrease in landings results from effective shark conservation measures or a decline in shark population abundance. Notably, with a slow growth rate, late age-at-maturity, and low fecundity, sharks have a limited ability to recover from depletion due to 3 unsustainable fishing practices.

The US National Oceanic and Atmospheric Administration (NOAA) manages commercial fishing for sharks through research, stock assessments, quotas, and restrictions when needed. NOAA Fisheries manages the shark populations in the Atlantic Ocean and Gulf of Mexico for commercial and recreational fishing and works with the Regional Fishery Management Organizations. When sharks are overfished, NOAA closes specific fisheries to rebuild the stocks to healthy levels.

Primary Threats to the Species The main threats to shark species are overfishing, incidental bycatch, habitat alteration / 1 disruption / disturbance, human-shark conflicts, and climate change . Specifically, sharks are caught as incidental take in tuna longline and groundfish fisheries, and they are targeted for their fins, meat, liver, skin, and cartilage. Trade in shark parts contributes significantly to the decline in shark abundance. Shark-fin soup is tied to deep-rooted 4 socio-cultural practices in Asia . A bowl of shark-fin soup can cost USD 100. Approximately 26 to 73 million individuals are harvested each year (worth USD 400-500 2,4 million) to supply the soup market . Other products derived from shark parts include pharmaceuticals from cartilage and oils from liver. The total value of these traded parts 4 from sharks is estimated to be USD 1 billion/year .

AZA Conservation Support Between 2012 and 2016, 42 AZA-accredited zoos and aquariums reported taking part in a variety of field conservation projects benefitting shark species. Over those five years, the AZA community invested over $14.1 million in shark conservation. Most projects were associated with population studies, conservation education, conservation-related research projects, and visual marker tagging. Visual marker tagging efforts in particular involved collaboration with the National Marine Fisheries Service, a division of NOAA, responsible for management of US marine resources.

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Dulvy, N. K. et al. Extinction risk and conservation of the world’s sharks and rays. Elife 3, e00590 (2014). FAO. International Plan of Action For the Conservation and Management of Sharks - Web site. Sharks. FI Institutional Websites (2014). at Dulvy, N. & Baum, J. You can swim but you can’t hide: the global status and conservation of oceanic pelagic sharks and rays. Aquat. … 482, 459–482 (2008). Clarke, S., Miler-Gulland, E. J. & Bjorndal, T. Social, economic, and regulatory drivers of the shark fin trade. Mar. Resour. Econ. 22, 305–327 (2007). Ferretti, F., Worm, B., Britten, G. L., Heithaus, M. R. & Lotze, H. K. Patterns and ecosystem consequences of shark declines in the ocean. Ecol. Lett. 13, 1055–71 (2010).