List of threatened rays

Manta rays include the largest rays in the world, and have been targeted by fisheries to the point where they have become vulnerable or endangered. In 2013 they were listed as CITES Appendix II species, which gives them some international protection.

The market for shark and ray products is first and foremost a luxury one: The gill plates, in the case of manta rays, are used in China for a tonic soup that has become fashionable because of perceived medicinal properties, even though it is not in the traditional Chinese pharmacopoeia. This is a recent trend and has caused a population loss of up to 86% in the last six to eight years.

WWF 2013

Threatened rays are those vulnerable to endangerment (extinction) in the near future. The International Union for Conservation of Nature (IUCN) ranks threatened species in three categories:

Vulnerable species
Endangered species
Critically endangered species

The term threatened strictly refers to these three categories (critically endangered, endangered and vulnerable), while vulnerable is used to refer to the least at risk of these categories. The terms can be used somewhat interchangeably, as all vulnerable species are threatened, all endangered species are vulnerable and threatened, and all critically endangered species are endangered, vulnerable and threatened. Threatened species are also referred to as a red-listed species, as they are listed in the IUCN Red List of Threatened Species.

Together rays and sharks make up the class of modern cartilaginous fishes. Modern fish are either cartilaginous or bony. Cartilaginous fishes have skeletons made of cartilage while bony fishes have skeletons made of bone. Because rays and sharks are closely related, they are often studied together. In 2010 a global IUCN study of vertebrates found that of 1,044 cartilaginous (ray and shark) species examined, 345 or 33% were threatened with extinction.

There are four orders of rays: stingrays, skates, electric rays and sawfishes. Like sharks, rays are relatively long living and thrive in stable populations. They are K-strategists which grow slowly, mature late sexually and produce few offspring. They cannot recover as rapidly as many faster growing fish can if their populations are depleted. As with sharks, rays are increasingly becoming vulnerable because of commercial and recreational fishing pressures, the impact of non-ray fisheries on the seabed and ray prey species, and other habitat alterations such as damage and loss from coastal development and marine pollution. Most particularly, the continuing decline of threatened rays and sharks is the consequence of unregulated fishing, as illustrated by a recent international survey which listed only 38 species of skates and rays still subsisting in the highly impacted Mediterranean Sea.

Sawfish are a family of rays which have a long rostrum resembling a saw. All species in the family are either endangered or critically endangered

Manta rays are largest rays in the world, with wingspans reaching 7 metres. They have one of the highest brain-to-body mass ratios of all fish. Manta populations suffer when they are caught as bycatch by fishermen fishing for other species, but fisheries which target manta rays are even more harmful. Manta rays use their gills to filter plankton from the sea. Demand for their dried gill rakers, cartilaginous structures protecting the gills, has been growing in traditional Chinese medicine practices. The market is "bogus" since dried manta gills have never been used historically in Chinese medicine, and there is no evidence that the gills have any medicinal value. The flesh is edible and is consumed in some countries, but is tough and unattractive compared to other fish. To fill the growing demand in Asia for gill rakers, targeted fisheries have developed in other parts of the world, including Sri Lanka, Indonesia, West Africa and Central and South America. Each year, thousands of manta rays, primarily the giant manta ray, are being caught and killed purely for their gill rakers. A fisheries study in Sri Lanka estimated that over a thousand of these were being sold in the country's fish markets each year.

In 2011, manta rays became strictly protected in international waters thanks to their recent inclusion in the Convention on Migratory Species of Wild Animals. The CMS is an international treaty organization concerned with conserving migratory species and habitats on a global scale. Although individual nations were already protecting manta rays, the fish often migrate through unregulated waters, putting them at increased risk from overfishing. In 2013, the Convention on International Trade in Endangered Species (CITES) listed both species of manta rays as CITES Appendix II species. This means that the international trade of manta rays will now be monitored and regulated.

Sawfish are a less well known family of rays which have a long rostrum resembling a saw. Some species can reach 7 metres or 23 feet in length. All species of sawfish are either endangered or critically endangered as a result of habitat destruction and overfishing. Their young stay close to shore, and are particularly affected by coastal developments. Because their rostrum is easily entangled, sawfishes can easily become bycatch in fishing nets. They are also exploited for the novelty value of their rostrum, their fins are eaten as a delicacy in China, and their liver oil used as a food supplement. While arguing for a global ban on international commerce in 2007, a representative from the National Museums of Kenya stated, "Only the meat is consumed locally; and artisanal fishermen can retire after catching one sawfish due to the high value of a single rostrum, up to $1,450." In 2013 CITES uplisted the largetooth sawfish to Appendix I. This is CITES highest protection level, and means that all international trade of the species is banned.

According to a 2021 study published in the journal Nature, relative fishing pressure in the oceans has increased by a factor of 18 since 1970. This overfishing has resulted in the number of oceanic sharks and rays declining globally by 71%, and has increased the global extinction risk to the point where three-quarters of these species are now threatened with extinction. Precautionary science-based catch limits and strict prohibitions are now needed urgently if population collapse is to be avoided, if the disruption of ecological functions is to be averted, and if a start is to be made on rebuilding global fisheries.

List

Order Image Scientific name Common name Population trend IUCN status Fish
Base
FAO Comment
Stingray Aetobatus flagellum Longheaded eagle ray decreasing Endangered
Stingray Aetomylaeus maculatus Mottled eagle ray decreasing Endangered
Stingray Aetomylaeus nichofii Banded eagle ray decreasing Vulnerable
Stingray Aetomylaeus vespertilio Ornate eagle ray decreasing Endangered
Skate Amblyraja radiata Thorny skate decreasing Vulnerable
Sawfish Anoxypristis cuspidata Knifetooth sawfish decreasing Endangered
Stingray Aptychotrema timorensis Spotted shovelnose ray unknown Vulnerable
Skate Atlantoraja castelnaui Spotback skate decreasing Endangered
Skate Atlantoraja cyclophora Eyespot skate decreasing Vulnerable
Skate Atlantoraja platana La Plata skate decreasing Vulnerable
Skate Bathyraja griseocauda Graytail skate decreasing Endangered
Electric ray Benthobatis kreffti Brazilian blind electric ray unknown Vulnerable
Stingray Dasyatis colarensis Colares stingray unknown Vulnerable
Stingray Dasyatis fluviorum Estuary stingaree decreasing Vulnerable
Stingray Dasyatis garouaensis Smooth freshwater stingray decreasing Vulnerable freshwater
Stingray Dasyatis laosensis Mekong freshwater stingray decreasing Endangered freshwater
Stingray Dasyatis margarita Daisy stingray decreasing Endangered
Stingray Dasyatis ukpam Daisy stingray unknown Endangered freshwater
Electric ray Diplobatis colombiensis Colombian electric ray unknown Vulnerable
Electric ray Diplobatis guamachensis Brownband numbfish unknown Vulnerable
Electric ray Diplobatis ommata Ocellated electric ray unknown Vulnerable
Electric ray Diplobatis pictus Variegated electric ray unknown Vulnerable
Skate Dipturus australis Sydney skate unknown Vulnerable
Skate Dipturus batis Blue skate decreasing Critically endangered
Skate Dipturus crosnieri Madagascar skate unknown Vulnerable
Skate Dipturus laevis Barndoor skate stable Endangered
Skate Dipturus mennii South Brazilian skate unknown Vulnerable
Skate Dipturus trachydermus Roughskin skate decreasing Vulnerable
Skate Glaucostegus granulatus Sharpnose guitarfish decreasing Vulnerable
Skate Glaucostegus thouin Clubnose guitarfish unknown Vulnerable
Skate Glaucostegus typus Common shovelnose ray decreasing Vulnerable
Skate Gurgesiella dorsalifera Onefin skate decreasing Vulnerable
Stingray Gymnura altavela Spiny butterfly ray decreasing Vulnerable
Stingray Gymnura zonura Zonetail butterfly ray decreasing Vulnerable
Electric ray Heteronarce garmani Natal electric ray unknown Vulnerable
Stingray Himantura gerrardi Whitespotted whipray unknown Vulnerable freshwater
Stingray Himantura hortlei Hortle's whipray decreasing Vulnerable freshwater
Stingray Himantura kittipongi Roughback whipray unknown Endangered freshwater
Stingray Himantura leoparda Leopard whipray decreasing Vulnerable freshwater
Stingray Himantura lobistoma Tubemouth whipray decreasing Vulnerable freshwater
Stingray Himantura oxyrhyncha Longnose marbled whipray unknown Endangered freshwater
Stingray Himantura pastinacoides Round whipray decreasing Vulnerable freshwater
Stingray Urogymnus polylepis Giant freshwater stingray decreasing Endangered freshwater
Stingray Himantura signifer White-edge freshwater whipray unknown Endangered freshwater
Stingray Himantura uarnacoides Bleeker's whipray decreasing Vulnerable freshwater
Stingray Himantura uarnak Reticulate whipray decreasing Vulnerable
Stingray Himantura undulata Bleeker's variegated whipray decreasing Vulnerable
Skate Leucoraja circularis Sandy ray unknown Vulnerable
Skate Leucoraja melitensis Maltese skate decreasing Critically endangered
Skate Leucoraja ocellata Winter skate decreasing Endangered
Stingray Myliobatis hamlyni Purple eagle ray decreasing Endangered
Skate Malacoraja senta Smooth skate decreasing Endangered
Stingray Manta alfredi Reef manta ray decreasing Vulnerable
Stingray Manta birostris Giant manta ray decreasing Endangered
Stingray Mobula mobular Giant devil ray decreasing Endangered
Stingray Mobula rochebrunei Lesser Guinean devil ray unknown Vulnerable
Electric ray Narcine brevilabiata Shortlip electric ray unknown Vulnerable
Electric ray Narke japonica Japanese sleeper ray unknown Vulnerable
Skate Okamejei pita Pita skate unknown Critically endangered
Stingray Pastinachus solocirostris Roughnose stingray unknown Endangered
Stingray Platyrhina sinensis Fanray unknown Vulnerable
Sawfish Pristis clavata Queensland sawfish decreasing Critically endangered
Sawfish Pristis pectinata Smalltooth sawfish decreasing Critically endangered
Sawfish Pristis pristis Common sawfish decreasing Critically endangered
Sawfish Pristis zijsron Narrowsnout sawfish decreasing Critically endangered
Skate Raja pulchra Mottled skate decreasing Vulnerable
Skate Raja undulata Undulate ray decreasing Endangered
Sawfish Rhina ancylostoma Bowmouth guitarfish decreasing Critically endangered
Sawfish Rhinobatos albomaculatus White-spotted guitarfish decreasing Vulnerable
Sawfish Rhinobatos cemiculus Blackchin guitarfish decreasing Endangered
Sawfish Rhinobatos formosensis Taiwan guitarfish unknown Vulnerable
Sawfish Rhinobatos horkelii Brazilian guitarfish decreasing Critically endangered
Sawfish Rhinobatos irvinei Spineback guitarfish decreasing Vulnerable
Sawfish Rhinobatos jimbaranensis Jimbaran shovelnose ray decreasing Vulnerable
Sawfish Rhinobatos obtusus Widenose guitarfish decreasing Vulnerable
Sawfish Rhinobatos penggali Indonesian shovelnose ray decreasing Vulnerable
Sawfish Rhinobatos rhinobatos Common guitarfish decreasing Endangered
Stingray Rhinoptera brasiliensis Brazilian cownose ray decreasing Endangered
Stingray Rhinoptera javanica Javanese cownose ray unknown Vulnerable
Skate Rhinoraja albomaculata White-dotted skate unknown Vulnerable
Sawfish Rhynchobatus australiae White-spotted guitarfish decreasing Vulnerable
Sawfish Rhynchobatus djiddensis Giant guitarfish decreasing Vulnerable
Sawfish Rhynchobatus laevis Smoothnose wedgefish unknown Vulnerable
Sawfish Rhynchobatus luebberti Lubbert's guitarfish decreasing Endangered
Sawfish Rhynchobatus sp. nov. A Roughnose wedgefish decreasing Vulnerable
Sawfish Rhynchobatus springeri Broadnose wedgefish decreasing Vulnerable
Skate Rioraja agassizii Rio skate unknown Vulnerable
Skate Rostroraja alba Bottlenose skate decreasing Endangered
Skate Spiniraja whitleyi Melbourne skate unknown Vulnerable
Skate Sympterygia acuta Bignose fanskate decreasing Vulnerable
Stingray Taeniura meyeni Round ribbontail ray unknown Vulnerable
Electric ray Temera hardwickii Finless sleeper ray unknown Vulnerable
Sawfish Trygonorrhina melaleuca Magpie fiddler ray unknown Endangered
Stingray Urogymnus asperrimus Porcupine ray unknown Vulnerable
Stingray Urogymnus ukpam Pincushion ray unknown Endangered
Stingray Urolophus bucculentus Sandyback stingaree decreasing Vulnerable
Stingray Urolophus javanicus Java stingaree decreasing Critically endangered
Stingray Urolophus orarius Coastal stingaree unknown Endangered
Stingray Urolophus sufflavus Yellowback stingaree decreasing Vulnerable
Stingray Urolophus viridis Greenback stingaree decreasing Vulnerable
Stingray Urotrygon reticulata Reticulate round stingray unknown Vulnerable
Stingray Urotrygon simulatrix Fake round ray unknown Vulnerable
Sawfish Zapteryx brevirostris Shortnose guitarfish decreasing Vulnerable
Skate Zearaja chilensis Yellownose skate decreasing Vulnerable
Skate Zearaja maugeana Maugean skate unknown Endangered

See also


This page was last updated at 2023-11-12 14:52 UTC. Update now. View original page.

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