Sharks need smarter management and better data to recover and thrive

By Amada44 (Own work) [GFDL ( or CC BY 3.0 (], via Wikimedia Commons

Dusky Shark  (Carcharhinus obscurus) are extremely rare. This one is swimming at Seaworld Aquarium in Queensland, Australia. Photo by: Amada44 via Wikimedia Commons

Shark advocates at Oceana recently sued the National Marine Fisheries Service (NMFS), claiming that the way the agency controls fishing on dusky sharks violates the Magnuson-Stevens Act.  Duskies are overfished and have suffered overfishing for years, even though it is illegal to retain them if they are caught.  The duskies’ plight highlights the shortcomings of bans and similar efforts when it comes to protecting vulnerable species like sharks, especially when they are caught alongside other, healthier species.

Over the last several years, more and more people have learned about both the importance of sharks and the ongoing threats to their existence. This is great news because sharks are among the most important creatures in the ocean, playing a vital role in maintaining healthy marine ecosystems.  Plus, they’re really cool.  Formerly of interest exclusively to fish geeks like myself, Shark Week is now a widely celebrated summer ritual.  Shark finning, a deplorable practice where a shark’s fin is removed and the rest of its body is discarded at sea, has been banned in the United States since 2000, and more than 70 other countries have enacted similar bans.

Despite this progress, shark populations remain threatened and overfishing is common. The FAO reports that the market for sharks has actually increased, and many sharks die as bycatch as a side effect of fishing for other species at healthier population sizes, such as Atlantic swordfish (which has recovered after a focused conservation effort).

Nineteen U.S. shark species, including duskies and great white sharks, are at such low population levels that they are so-called “prohibited” species; if caught, they cannot be kept.    For dusky sharks, the ban has been in place since 2000.  Nevertheless, they have continued to experience overfishing.  Duskies simply can’t tolerate much fishing and struggle to recover because they don’t reproduce until about 20 years of age and then deliver 5-10 pups only once every three years.  NMFS calculates that in order to rebuild them in a century — 100 years — fishing levels have to drop by more than half.

In short, the ban isn’t working.  Pretending sharks don’t get caught because we prohibit landing isn’t effective.  Even if increasing the use of conventional management tools, such as closed areas or gear restrictions, worked to curtail fishing mortality enough, those restrictions could force U.S. fishing vessels out of the fishery altogether.  But the foreign-flagged vessels can have even higher levels of bycatch, so importing more seafood could further harm the sharks we’re trying to protect.

We need a new approach.  Fortunately, emerging technologies could provide the means to effectively monitor and enforce real bycatch limits, and conservation incentives can lead to more flexible regulatory structures that give fishermen the ability and motivation to use their expertise to avoid the sharks.  Fishermen will have a stake in the recovery of the dusky population by minimizing the catch of the species and its impact on their ability to fish.

We’ve seen this kind of transformation in the west coast groundfish fishery.  After years of high levels of fishing mortality (and extensive litigation) that left many groundfish species extremely overfished, the long-lived species faced rebuilding plans that in some cases ran to more than 100 years.  The Pacific groundfish individual fishing quota program, which involves binding quotas of both targeted and bycaught species and careful monitoring, took effect in 2011.  The conservation results have been amazing.  Bycatch declined from roughly 20-25% of catch to less than 5% in 2011-2015.  2014 fleet-wide catch for overfished species was well below allowable limits.  Overfished populations have rebounded much more rapidly than expected.  Producing similar results for duskies and other sharks would be game-changing.

On the east coast and in the Gulf of Mexico, pelagic longline fishing vessels already carry cameras that monitor their fishing activities, and they tally their catch under a new system designed to protect Atlantic Bluefin tuna.  These changes are not easy to navigate, and fishermen deserve support and credit for doing so.  NMFS should carefully examine the lessons learned in the Atlantic Bluefin tuna effort and consider expanding it to other species, including dusky sharks.

Nor should American fishermen bear burdens that foreign fleets do not.  The United States has often broken new ground in fisheries management.  As solutions emerge for species like sharks that are caught all over the world, we can leverage our participation in international fishery management organizations to institute global management that takes into account the need to catch target fish while avoiding more vulnerable species.

Oceana has highlighted an important issue, and the law backs them up, as we explained in a letter to the agency back in January.  Pretending we can ban our way out of the deadly problem of shark bycatch has failed and violates the Magnuson-Stevens Act.  We hope the lawsuit leads to a stakeholder-driven process to develop real solutions.

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