Politics posing as shark science

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Politics posing as shark science

Fri, 27/08/2021 - 17:02
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Another piece of pro-shark-fishing propaganda has been published in the form of a ‘scientific’ paper (Shiffman et al. 2021). While promoting commercial shark fishing and the shark fin trade, it belittles shark conservationists by claiming that their approach to shark conservation is lacking in scientific knowledge.

Leaving aside the question of why shark scientists would work to undermine shark conservationists, its simplistic assertion focuses on just two unrelated subjects: the efforts to ban the shark fin trade, and the existence or not, of sustainable shark fisheries.

But science is not binary, and a brief perusal reveals that this is not a scientific paper but a political attack. The two Bills proposing to cope with the problem of shark depletion that are currently before the government of the USA address these exact points. The Shark Fin Sales Elimination Act of 2017, has been passed by the Senate and would effectively remove the USA from the shark fin trade, while The Sustainable Shark Fisheries and Trade Act of 2018 is the shark fishing industry’s solution. It would allow America’s shark fishermen to continue to profit from the shark fin trade and there is strong political pressure to push it through (Gehan 2019).

The first author of the present paper, David Shiffman, supports it. A long-term promoter of shark fishing, he has strongly criticized the Shark Fin Sales Elimination Act, and promotes the shark fin trade (Shiffman & Hueter 2017). The theme of this paper of belittling conservationists is common in his writing. Indeed, he is not a shark scientist; he is a shark fisheries scientist.

Though the idea of fishing sharks sustainably does indeed sound like a good one, when one looks into the practical details of the Sustainable Shark Fisheries and Trade Act, it is clear that there is no way to implement it. The shark fisheries that have been sustainably managed are only a few in North America and Australia that have traditionally fished sharks, skates, or rays for meat, but no commercial shark fishery serving the shark fin trade has ever been sustainable.

To anyone who has mastered the basics of subtraction, it is clear that sustainable shark fisheries could never serve the secretive, largely criminal shark fin trade (Dent & Clarke 2015).

The Sustainable Shark Fisheries and Trade Act

This bill involves putting American practices into play on a global scale. But the detailed recording and international cooperation that would be necessary would seem prohibitively difficult. Fisheries management schemes are expensive to set up and operate. Expenses range from those for scientific advice, research, and management, to enforcement—including monitoring, control, and surveillance—which can cost 14% of the value of the landings. Most of the cost is borne by the public sector, while the benefits are concentrated on the fishermen (World Bank 2017; Ferretti et al. 2020).

Countless details remain unaddressed, never mind resolved:

  • How would the determination of what is a sustainable catch rate for every shark fishery in the world be made?

  • How would the baseline be determined? (The mere assumption that it is possible goes well beyond what we know at present.)

  • How would sustainable fisheries’ management plans be implemented throughout every shark fishery in every country that fishes sharks?

  • How would they be funded?

  • How would they be enforced?

  • How would every country in the world with a shark fishery be lobbied to pass sustainable shark fisheries management legislation?

  • How would regional fisheries management organizations be made to agree to base quotas and rules solely on scientific recommendations without a few countries deciding to veto science-based recommendations, as happens already in other contexts on economic grounds?

  • How long would all this take, how much would it cost, and who would pay for it?

Massive data collection projects would need to be organized, which would have to be standardized, implemented, monitored, and funded on a global scale. Then, when laws are in place and enough data has been collected to determine what the sustainable catch rates might be for every shark fishery in the world, development and funding of fisheries’ management plans would need to be put in place, including staffing and training, purchase of equipment, and so on.

All this would need to be maintained long-term, while somehow requiring every country to keep politics, financial self-interest, and corruption, to say nothing of criminality, out of the process. But there is no international body that can force sovereign countries to do anything on this scale. Further, some countries, especially those with large fisheries, have consistently been resistant to controls on fishing based on scientific data.

The evidence for sustainable commercial shark fishing

The current fisheries hype over sustainable commercial shark fishing is based on the paper Bright spots of sustainable shark fishing (Simpfendorfer & Dulvy 2017), one of the co-author’s former papers, and cited here as the needed evidence of sustainability in shark fishing. But it was proven to be optimistic at best or false at worst, just two years after it was published. Among other things, it claimed that the shortfin mako fishery in the North and South Atlantic (and that of the blue shark) could be sustainably managed. But at the same time, scientists of the International Commission for the Conservation of Atlantic Tunas (ICCAT) found that the status of the mako shark was so dire that even if all fishing was stopped immediately, its numbers would continue to decline for the next fifteen years. There was a probability of only about 50% that the stock would be rebuilt by 2045, and the probability that it would be rebuilt would not exceed 70% until 2070, 50 years from now (ICCAT 2019).

Yet industrial fishing for the mako shark continues in the Atlantic, and the situation is considered to be similar for the blue shark.

The North Atlantic, right in the heart of the “civilized” world, should be the very epitome of excellent fishing management and sustainable shark fishing. But the truth is far from that. The sharks in the North Atlantic are managed by ICCAT, which represents 48 contracting nations and groups, including the European Union. Member nations provide data of highly variable quality for their fisheries and there are also several major fishing nations fishing the North Atlantic that provide no shark catch data to anyone, and are not party to ICCAT. It is estimated that only a quarter of the sharks killed there are reported, and that illegal finning is rampant (Campana 2016).

Yet, Shiffman et al. write:

Results show that in general, the environmental advocates who most strongly supported bans on fisheries and trade were the least familiar with the current state of scientific knowledge on sustainable shark fisheries.”

But it seems to be Shiffman et al. who are out of touch with the current state of scientific knowledge on sustainable shark fisheries.

Contrary to what the authors state, there is much scientific evidence which throws into question the idea that sustainable commercial shark fisheries are possible long term (for a summary see Porcher et al. 2019). An example is a study cited by this present paper as providing basic evidence of the existence of sustainable shark fisheries (Walker 1998). But instead of establishing the presence of plenty of sustainable shark fisheries, it questions whether sustainability can be realized and focuses on the difficulties of doing so. Further, it was written before the shocking results of the shark fin trade became evident.

The only other paper which the authors cite as evidence that sustainable shark fisheries exist is Shiffman’s own paper (Shiffman & Hueter 2017) in which he claimed that they exist all over the world, but provided no evidence that they do.

So in fact, the evidence these authors provide on the subject is flimsy.

Divers are “marine tourists”

Reading through the paper we find the claim that the public is concerned about sharks because they “can be ecologically important” and that they “are a popular encounter for scuba divers and other marine tourists.

This extreme twisting and misrepresentation of the facts is typical of the paper. All scientific studies of sharks in the biosphere have found that, as top and middle predators, they are among the most strongly interacting animals in the food chain. Several studies have shown that the extreme disruption wrought by more than seven decades of shark removal through trawling and long-lining has caused major, cascading biodiversity shifts throughout the originally complex and diverse aquatic ecosystems which evolved during the 500 million years before industrial fishing began.

However, fisheries have never been concerned about the ecological results of their activities (Travis et al. 2014). And the way this paper discounts and dismisses this important facet of shark removal reflects that.

Terming divers as “marine tourists” disparages a major force behind shark conservation efforts. A high fraction of divers dive locally all the time and know their area well. They are the ones who have personally witnessed the disappearance of sharks from the oceans and coasts the way the buffalo vanished from the plains of North America during the 1800s. For this reason, divers have always been at the forefront of shark conservation efforts, and their contributions are highly valued by anyone truly concerned about the plight of sharks.

Conservationists are extremely knowledgeable scientifically

The results of the survey on which this paper is based show that two thirds of NGO employees read scientific papers regularly and more than half have published scientific papers. This was found even though the authors deliberately excluded scientists from the survey. NGOs were found to use scientific and not moral reasons for their arguments for shark protection. Remarkably, only 4 respondents out of 155 reported never reading the scientific literature.

So the conclusion of the paper should have been that NGOs working on shark conservation are very knowledgeable scientifically, rather than the contrary.

Beliefs more important than facts

In 2016, Dan Kahan and his team at Yale Law School made headlines when they found that people will fail to question their beliefs in the face of scientific discoveries that contradict them. Their study showed how people reason selectively, and interpret data in such a way that it conforms with their political vantage point. Scientists are even more prone to this than others and the phenomenon is clear to see in the sustainable shark fisheries’ lobby. Regardless of the facts, their conclusions always favour fishing more sharks.

The situation parallels the way two decades of scientific findings that fish feel pain and suffer are sneered at and denied by fishermen (Sneddon et al. 2018). As a result, most people seem to believe that no matter how you brutalize them, fish and sharks will not suffer, so their abuse continues with almost no public outcry nor protest. Yet there has never been any evidence that fish do not feel pain—it is just an assumption based on their lack of a human brain.

In fact, the pain system in fish is remarkably similar to our own and if it did not work, they would not have it. Indeed, no one who has watched a fish eat a sea urchin will doubt their sensitivity.

The status of sharks based on science

Detailed analyses of fishing records show that the shark species accessible to global fisheries have been systematically depleted since industrial fishing began in the 1950s. By 2003 they had sunk to about 10% of their former levels. Industrial fisheries originally targeted teleost fish, so sharks were mostly discarded with no record being kept. But, with the rise in value of shark fins due to the shark fin trade, at the same time as teleost fish stocks were depleted, sharks (along with tuna) became the most valuable catches (Sala et al. 2018) and are now being targeted by fisheries around the world.

The shark fin trade is driven by enormous profits and there is no interest in sustainability in either the shark fin industry or consumer countries (Sadovy de Mitcheson et al. 2018), where neither the will nor the resources to manage the trade exist. With the global demand for shark fins rising while the large predators supplying that demand are at a tiny fraction of their former numbers, and increasingly threatened with extinction, commercial fishing for sharks is clearly unsustainable.

Worldwide studies of overfishing have repeatedly called for a reduction of the fishing effort to allow fish stocks and their habitat to recover. But turning to fishing the predators now that the teleost fish are 90 percent depleted is folly (World Bank 2017; IPBES 2019; Dasgupta 2021).

It is a no-brainer really, for no wild animal can withstand targeted industrial-scale hunting long term—not whales, not sea turtles, not fish, and certainly not sharks.

But philosophical pro-shark fishing propaganda, of a type neglecting biological fact, is working hard to see that they never get the protection that they so urgently need.

Ila France Porcher (c) 2021

Author of The True Nature of Sharks and The Shark Sessions


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