One Quarter of Sharks and Rays Threatened with Extinction

A quarter of the world's sharks and rays are threatened with extinction, according to IUCN Red List™ criteria, with rays at greater risk than sharks

PRESS RELEASE | Gland, Switzerland | January 21, 2014

Pelagic Thresher Shark (Alopias pelagicus) © Bo Mancao

The findings, published today in the journal eLife, are part of a global assessment of 1,041 species conducted by the IUCN Shark Specialist Group. Ray and sharks are at substantially higher risk than most other groups of animals and have the lowest percentage of species considered safe. Overfishing is the main threat.

"Our analysis shows that sharks and their relatives are facing an alarmingly elevated risk of extinction," says Dr. Nick Dulvy, IUCN SSG Co-Chair and professor at Simon Fraser University. "In greatest peril are the largest species of rays and sharks, especially those living in shallow water that is accessible to fisheries."

Reported shark, ray, and chimaera catches peaked in 2003 and have been dominated by rays for 40 years. Unintentionally caught sharks and rays account for much of the catch, yet developing markets and depletion of targets have made this "bycatch" increasingly welcome.

​"We have found that the rays -- including sawfishes, guitarfishes, and stingrays -- are generally worse off than the sharks, with five out of the seven most threatened families made up of rays," says Dr. Colin Simpfendorfer, IUCN SSG Co-Chair and professor at James Cook University. "While attention to the plight of sharks is growing, the widespread depletion of rays is largely unnoticed. Conservation action for rays is lagging far behind, which only heightens our concern."

​Demand for shark fin soup is a major factor in the depletion of sharks and some rays.  Sharks, rays, and chimaeras are also sought for meat, and other products. Safeguards are generally lacking.

"Sharks, rays, and chimaeras tend to grow slowly and produce few young, leaving them particularly vulnerable to overfishing," says Sonja Fordham, IUCN SSG Deputy Chair and president of Shark Advocates International. "Significant policy strides have been made, but effective conservation requires a dramatic acceleration in pace as well as an expansion of scope to include all shapes and sizes of these exceptional species. The need for such action is urgent.

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The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. The first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes (sharks, rays, and chimaeras) was published in the journal eLife in 2014.

​This paper estimated that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall, chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world’s ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery.

Media Release

• IUCN Press Release: This eLife paper was released at the start of the year marking the 50th anniversary of The IUCN Red List. The findings are part of the first ever global analysis of these species carried out by the IUCN Shark Specialist Group (SSG).
• PRNewswire-USNewswire
• YouTube Video Summarizing Findings: SSG Co-Chairs and authors on the eLife paper, Nick Dulvy and Colin Simpfendorfer, summarize the findings of the eLife paper in this short video abstract. 
• Infographic
• Fact Sheet, for an updated Fact Sheet Table click here
• Higher resolution images are available here.
• A summary of other media releases are available here
• The IUCN has developed "Amazing Species" profiles for the Giant Guitarfish (Rhynchobatus djiddensis), the Smooth Hammerhead Shark (Sphyrna zygaena), the Great Hammerhead Shark (S. mokarran), the Horn Shark (Heterodontus francisci), and the Dusky Smoothhound (Mustelus canis).

Reference

• ​Dulvy, N. K., Fowler, S.L., Musick, J.A., Cavanagh, R. D., Kyne, P. M., Harrison, L. R., Carlson, J. K., Davisdson, L. N. K., Fordham, S.V., Francis, M. P.,  Pollock, C. M., Simpfendorfer, C. A., Burgess, G. H., Carpenter, K. E., Compagno, L. V. J., Ebert, D. A., Gibson, C., Heupel, M. R., Livingstone, S. R., Sanciangco, J. C., Stevens, J. D., Valenti, S. and White, W. T. 2014. Extinction risk and conservation of the world's sharks and rays. eLife: eLife 2014;3:e00590.

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Images and Captions for Media Use

Below are photos for use by media if appropriately credited.

Download high resolution images here.

Here is  brief guide to the kind of images available:

• First , the threatened (Critically Endangered, Endangered and Vulnerable) species
• Second, Near Threatened and Least Concern species
• Third, fisheries catches, fish processing and landing sites.

Species Listed as Critically Endangered

Research on chondrichthyans, including this Critically Endangered Northern River Shark (Glyphis garricki), is providing information for management and recovery of threatened species. Photo Credit: Grant Johnson.

The Critically Endangered and ironically named Common Skate (Dipturus batis) reaches a maximum length of 2.5 m. This egg-laying ray, and others like it, has been eliminated from shallow temperate seas throughout its range an is only found in a few deepwater places and rocky habitats that are too difficult to trawl. Photo Credit: Scottish Sea Angling Conservation Network (SSACN).

The Critically Endangered Angel Shark (Squatina squatina) has almost disappeared from European waters and can now only be found with any regularity in the Canary Islands. It was formerly a common and important bottom-dwelling predator over large areas of its coastal and outer continental shelf sediment habitat in the Northeast Atlantic, Mediterranean and Black Seas. Most of this region is now subject to intense demersal fisheries, and the species is highly vulnerable (from birth onwards) to bycatch in the benthic trawls, set nets and bottom longlines operating through most of its range and habitat. Photo Credit: Tony Gilbert.

Species Listed as Endangered or Vulnerable

The Great Hammerhead Shark (Sphryna mokarran) is a large, widely distributed, tropical shark largely restricted to continental shelves that is listed as Endangered. It is highly valued for its fins (in target and incidental fisheries), suffers very high bycatch mortality and only reproduces once every two years, making it vulnerable to overexploitation and population depletion. Photo Credit: Neil Hammerschlag.

Guitarfishes and wedgefishes are among the most threatened rays, due to the high value of their large fins. This Whitespotted Wedgefish (Rhynchobatus djiddensis) reaches over 3 metres long and is classified as Vulnerable by IUCN. Photo Credit: Matt D. Potenski.

The Shortlip Electric Ray (Narcine brevilabiata) from Sarawak, Borneo Indonesia is listed as Vulnerable by IUCN. Photo credit: Australian National Fish Collection, CSIRO.

The Pelagic Thresher Shark (Alopias pelagicus), at Monad Shoal, near Malapascua Island in the Visayan Sea of the central Philippines. This species is listed as Vulnerable on the IUCN Red List of Threatened Species. Photo credit: Bo Mancao.

Juvenile Giant Shovelnose Ray (Glaucostegus typus) Heron Island, Great Barrier Reef, listed as Vulnerable by IUCN. Photo Credit: Michelle Heupel, Australian Institute of Marine Science.

Species Listed as Near Threatened

The Mangrove Whipray (Himantura granulata) at Ningaloo Reef Marine Park, Western Australia s listed as Near Threatened by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

The Whitetip Reef Shark (Triaenodon obesus) from Sipadan Island, Borneo, Indonesia is listed as Near Threatened by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

The Bluespotted Maskray (Taeniura lymma) from Bali, Indonesia is listed as Near Threatened by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

The Near Threatened Mangrove Whipray (Himantura granulata) resting in mangrove roots, Orpheus Island, Great Barrier Reef. Photo Credit: Michelle Heupel, Australian Institute of Marine Science.

Species Listed as Least Concern

The Port Jackson Shark (Heterodontus portusjacksoni) from Perth, Western Australia s listed as Least Concern by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

The Smooth Stingray (Dasyatis brevicaudata) from Rottnest Island, Western Australia is listed as Least Concern by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

Tasmanian Numbfish (Narcine tasmaniensis) from Derwent Estuary, Hobart, Tasmania is listed as Least Concern by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

Banded Stingaree (Urolophus cruciatus) from Tasmania is listed as Least Concern by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

Fisheries Catches and Landing Sites

Some of the most threatened species, including rays and skates, have declined due to incidental capture in fisheries targeting other species This Blue-spotted Maskray (Neotrygon kuhlii), caught as bycatch in a prawn trawl fishery, is listed as Data Deficient by IUCN. Photo Credit: Peter Kyne.

Wedgefish and Sawfish landings at Muara Angke, Jakarta, Indonesia. Species of these shark-like rays are highly valued for their fins and are listed as Endangered and Critically Endangered by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

Wedgefish (Rhynchobatus spp) landings at Muara Angke, Jakarta. Species of this shark-like ray family are listed as Vulnerable and Endangered by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

A species of Devil Ray (Mobula spp.) having its gill rakers removed at a fishing port in Sri Lanka. The gill rakers of devil rays and closely related mantas are valuable for use in Chinese medicine. Photo Credit: Sonja Fordham.

Thresher Shark fins at processing centre at Cilacap, Central Java, Indonesia. All three Thresher Shark species are listed as Vulnerable by IUCN. Photo Credit: Australian National Fish Collection, CSIRO.

Deepwater shark and ray catch at Cilacap, Central Java, Indonesia. Deepwater sharks and rays are increasingly threatened as fisheries deplete the shallow coastal seas and move into deeper waters. Photo Credit: Australian National Fish Collection, CSIRO.

Shark trunks being weighed and logged at Muara Baru, Jakarta. Photo Credit: Australian National Fish Collection, CSIRO.

Daily shark landings being auctioned at Tanjung Luar, Lombok. Photo Credit: Australian National Fish Collection, CSIRO.