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Abu Dhabi, UAESunday 24 June 2018

Sharks become victims of most deadly predator in the Gulf - overfishing

New report says the fishing industry is pushing many species towards extinction

Sharks for sale in the UAE. Over-fishing of various species has led to them becoming endangered. Antonie Robertson / The National
Sharks for sale in the UAE. Over-fishing of various species has led to them becoming endangered. Antonie Robertson / The National

It looks like a fearsome predator of the seas. Nearly two metres long when fully grown, hunting with 15 rows of sharp teeth and its presence announced by the dreaded triangular fin carving through the water.

In fact, we have nothing to fear from the Smoothtooth Blacktip shark, which lives largely in the Arabian Gulf and dines exclusively on smaller fishes. The real danger is mankind, which is pushing the species to the brink of extinction.

Over-fishing and habitat destruction has caused a worrying decline in almost half the species of sharks, rays and similar species according to a new report, released in conjunction with Environment Agency Abu Dhabi.

The Smoothtooth Blacktip Shark, which once thrived in the shallow waters of the Gulf, is one of three species of the chondrichthyan family now placed on the endangered list by the International Union for Conservation of Nature.

The regional “Red List” report is the first of its kind and concludes that the Arabian Sea and its adjacent waters, which include the coastline of the UAE, are “home to some of the most threatened chondrichthyan populations in the world.”

Out of 153 species recorded, 78 are considered threatened to some degree. Three are listed as critically endangered, including the Stripenose Guitarfish, which lives at the bottom of the sea and is vulnerable to modern trawler fleets, and the Red Sea Torpedo, another ray, which was last seen in 1898 and is possibly extinct.

The report, in collaboration with the IUCN and EAD, hopes to establish a regional base list for the chondrichthyan family, which includes sharks, rays and sawfish, and which are distinguished by having skeletons made of cartilage rather than bone.

It found only 19 species whose numbers could still be considered healthy, while there was not enough data to reach a conclusion on around 30 more. So little is known about populations that some species are still being identified. Vivaldi's Catshark, which lives in deep water off Somalia, was only declared a new species in May, over 125 years after the first specimens were caught.

"Nothing is known of its population size, structure and biology," the report concludes.

"We are all concerned about the long-term survival of many species of sharks and rays in our region and these results provide an important baseline for monitoring their status,” said Dr Rima Jabado, Fisheries Scientist at EAD.

“Relevant stakeholders across the region need to work closely together to ensure immediate actions are taken to halt and reverse these declines.”

While several of the species are deliberately targeted by the fishing industry, other sharks and rays get swept up in nets accidentally, known as “by-catching”.

Scientists say that these kind of fish are particularly vulnerable because of their biology and reproductive patterns.

"Sharks, rays and chimaeras tend to grow slowly and produce few young, which leaves them particularly vulnerable to over-fishing", said Dr Peter Kyne, Senior Research Fellow at Charles Darwin University and Red List Authority for the IUCN Shark Specialist Group.

Other threats include coastal development projects and damaged to habitat, such as mangroves and coral reefs.

The area studied ranged from the Red Sea coasts of Egypt and Saudi Arabia, to Somalia and India and Pakistan. It includes all the GGC countries.

The report calls for a more joined-up approach to conservation, with better research and policy making by governments in the area. It also calls for limits on catches and sizes, with seasonal closures of fisheries and what it calls “meaningful penalties for violations," although it says countries like the UAE have shown more awareness of the problem. Measures introduced by the EAD include escape panels and minimum sizes for mesh in nets that allow smaller, juvenile, fish to escape.

There are also concerns that the number of fish caught in the region is severely under-reported. One study, by a Canadian university, concluded that the amount of fish caught between 1950 and 2010 in the Gulf was double that reported by the UN Food and Agriculture Organisation.

Dr Shaikha Al Dhaheri, the EAD’s Executive Director, Terrestrial and Marine Biodiveristy Sector, called the study: “The first step in understanding the regional status of sharks and rays, adding that: “The results are a call for action and highlight the urgent need for regional cooperation in research and policy efforts."