Sharks

Why do we worry about shark populations? They may rule the ocean, but sharks are an incredibly vulnerable species. Because they grow slowly and produce few young, sharks are exceptionally susceptible to overexploitation. Further, a healthy and abundant ocean and the communities that rely on it depend on healthy shark populations. Living sharks can help fuel local economies in places like Palau, where sharks bring in an estimated $18 million per year through dive tourism.

Overexploitation, through targeted as well as incidental catch, is one of the main global threats facing shark survival. Overfishing is driving sharks to the brink of extinction - with many populations down by 80 percent. Tens of millions are killed each year for their meat, fins, liver, and other products, as many fisheries are unregulated and catches are significantly under-reported. Bycatch – catching sharks incidentally and indiscriminately while fishing for other commercial species – poses a significant threat to sharks. At the same time, new markets for shark and ray products are blurring the line between targeted and accidental catches. Finning – the removal of shark fins and discard of the shark’s body at sea - is often associated with shark overfishing, as keeping only the fins aboard the vessel allows fishermen to kill many more sharks than if they were required to bring back the entire animal. Fueling this practice is the fact that shark fins yield a much higher price than shark meat, providing an economic incentive for the wasteful and indefensible practice of finning.

Devil and Manta Rays

As slow moving, often predictable, filter feeders, rays are easy targets. According to data collections by the Food and Agriculture Organisation (FAO), Mobulid landings have increased over the past decade. As with shark landings, it’s expected that reported Mobulid landings only account for a small fraction of the actual number of mortalities related to fishing. Old and new markets for meat and other ray products such as gill plates – the tight-knit, feathery structures they use to strain plankton and small fish  - threaten the survival of devil and manta rays.

Mantas, in particular, are at the top of many divers’ must-see list. Operations that offer manta diving and swimming programs are increasingly profitable and bring significant economic benefits to coastal communities across the globe. According to the Manta Ray of Hope project, the estimated worldwide value of manta-based tourism and filming is as high as $100 million USD each year.

Devil and manta rays are at particular risk to overfishing because they are estimated to produce a single pup every one to three years. Many populations have already been depleted by unregulated fishing. Recently, International trade in mantas has been regulated and they are legally protected in some nations and specific aggregation areas. Implementation and enforcement, however, are sorely lacking in most places while fishing for devil rays - mantas’ less charismatic cousins – is left mostly unmanaged with even fewer safeguards in place.

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