The science of sustainable seafood, explained

George Burgess


George Burgess, an ichthyologist and fisheries biologist, is the Director of The Florida Program for Shark Research (FPSR) and Curator of the International Shark Attack File and International Sawfish Encounter Database, both of which are headquartered at University of Florida’s Florida Museum of Natural History. George has studied fishes and elasmobranchs throughout the world. He serves as a Vice Chairman of the IUCN Shark Specialist Group and works with ICCAT and other fishery initiatives.

Sustainability of shark fisheries

I spoke with George Burgess, the Director of the Florida Program for Shark Research about the status of shark populations and the sustainability of shark fisheries. “Sharks are classic ‘life in the slow lane animals’”, George says, meaning they are long-lived, late to reach sexual maturity and have limited reproductive potential. “As a result, when these animals are overfished, they’re recovery, even if done with proper fisheries management, is usually measured in decades rather than years” (00:34). This means sharks and their relatives the skates and rays are more sensitive to overfishing than most bony fishes, with the exception of some long-lived species such as rockfish.

Despite having overfished sharks on both coasts of the U.S., management measures put in effect over the last decade or so are allowing recovery of most of these species. “But,” George cautions, “some of them are still two or more decades away from getting back to the levels that we might like them” (02:40). This leads to the question: Are these shark fisheries sustainable? “The answer to that question is yes they are, but they are sustainable at levels lower than perhaps folks would like in the fishing community” (04:02). George believes that the fishing sector has learned its lesson multiple times with ‘boom and bust’ fisheries, and having heavily fished elasmobranch stocks that then suffered the inevitable crash, “we should be smarter now and be able to manage in a sustainable way, just at lower levels than what we have in the past” (04:28). George attributes the U.S.’s poor track record of demonstrating long term sustainability to the development of fisheries before the management; “we’re closing the barn door after the horse has gotten out” (07:28).

When it comes to management, “every species of shark and ray has its own demography and needs to be regulated according to its life history parameters” (05:00). Early attempts at management in the U.S. considered sharks as a single unit. Once shark populations began crashing, “the scientific world came to the sad realization that we were decades behind getting the information we needed on a species-by-species basis” (05:25). “Shark biologists have been playing catchup for the last couple of decades, and we’re now starting to get better and better information. Models and so forth that are traditionally used in developing appropriate fisheries management measures are now becoming more species-specific and a lot more useful” (06:20).

With this in mind, what does a sustainable shark fishery look like? According to George, spiny dogfish “are particularly suitable for good fishery management because they are found in large numbers and they have high economic value.” Spiny dogfish fisheries “have traditionally been very valuable for their flesh, which is highly prized particularly in western Europe – it was the staple for fish and chips for years” (07:50). When the fishery off the NE Atlantic became overfished due to demand of the many fishing nations of Europe, “a fairly large fishery developed off of the U.S. coast for export, and the inevitable result was that we did the same thing that the Europeans did – we didn’t learn from their mistakes, and those populations declined dramatically” (09:12). The stock has been rebuilt due to stringent management implemented in 1998 after NMFS declared spiny dogfish overfished.

Other sharks, by contrast, are found in less dense populations and are targeted not for their flesh, but for their fins, which are sent to Asian markets to be made into shark fin soup. “Economically, on a pound-for-pound basis, I do believe that shark fins are worth more than any other fish outside of bluefin tuna. That’s the economic motivator for shark fisheries” (11:25). These sharks are often not specifically targeted. Instead, they are caught as bycatch of other fisheries, most notably open-sea fisheries where international waters are not regulated or enforced, such as tuna and swordfish fisheries. “The fins from these sharks are now the icing on the cake for fishers in those fisheries. Formally considered just a pain in the neck,…[fishermen] generally cut them off [the line] and threw them back overboard dead or alive; they now have intrinsic value dead for their fins” (12:02). In some quarters, fishers began to save the fins and discard the carcasses – often alive but sans fins, a wasteful and inhumane practice known as “finning.”  “Happily, there’s been a lot of action on both national and international levels to curtail that activity. Most countries now have anti-finning regulations which are usually enacted by having the correct number of fins landed with the correct number of carcasses” (12:55).

What does this mean for the future of shark fisheries management? “Most species of sharks are highly migratory, so they don’t honor geopolitical boundaries. The problem with fishery management of sharks like other highly migratory species is that they require international conservation and management. Much like bluefin tuna, there’s will be a lot of contention on how we manage these animals on a global basis because so many species are cosmopolitan. It’s hard enough to get agreement among biologist from one country…but now you throw in multiple countries in different languages and different cultural morays and so forth, so you have a more complex situation” (15:50).

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4 Responses

  1. There exists a carefully controlled and stringently regulated Legitimate Shark Fishery! However, making inaccurate and misleading generalized statements about sharks and shark “finning” and how, unless carefully scrutinized, “fishers will sneak in extra fins”, and in particular, making silly statements about Spiny Dogfish as “high value”, therefore implying the reason they were “overfished”, has created a perception of commercial fishing as greedy and uncaring plunder, a villification which typically leads to baseless regulations. Such regulations are destructive to the fish and to the fishermen. They can, and often do, prevent legitimate harvesting of a vital healthy food source and they create destructive imbalances hostile to the entire ecosystem. For example, the meager Dogfish landing allocations have seen that population along with Smooth Skates proliferate and dominate other important Northeast species.

    Statements, in this “Shark Week” interview, such as spiny dogfish “…are particularly suitable for good fishery management because they are found in large numbers and they have high economic value”, are false and misleading. Spiny Dogfish are found in large numbers all right, in fact they are vacuuming up the Cod, Haddock, Flounder, and everything else in their path—but “high economic value”…?

    I don’t mean to cast aspersions on anyone’s knowledge regarding the economics of commercial fishing, but the price to fishermen for Spiny Dogfish was never more than 25 cents per pound between the years 2000 thru 2014, and was less in the preceding decades and it is currently somewhere less than 15 cents per pound; this is according to the body that recommends quotas for this species, the Mid-Atlantic Fisheries Council http://www.mafmc.org/dogfish/

    (Please see Fig. 4 and Fig. 5 in the report to the council on Spiny Dogfish:


    And from an article in the Portland (Maine) Press Herald on Spiny Dogfish: “Two trends are moving in opposite directions: The species’ population is increasing while its commercial value is falling. Fishermen are paid around 14 cents a pound for them.”

    “And here’s the problem: Scientists say there are huge and growing numbers of dogfish in the Gulf of Maine competing for the same food as more commercially valuable species, such as cod and haddock.”

    “’Their numbers are enormous,’ said James Sulikowski, a biologist at the University of New England who has studied the species for years. ‘Dogfish have to eat. If they are strong and increasing in population, they will eat a lot of stuff. That stuff is what other species feed on as well.’”

    “He said there are an estimated 230,000 metric tons of spawning dogfish – females of reproductive age – in the Gulf of Maine, compared with only 10,000 metric tons of spawning cod. That’s a 23-to-1 ratio.”


    So the truth is that there has never been any “high economic value” when it comes to Spiny Dogfish. And please, it’s not about the “…fishing sector has learned its lesson multiple times with ‘boom and bust’ fisheries” that paternalistic stance is also inaccurate and misleading. Independent small boat family fishermen have the greatest interest in the sustainability of the stocks that they rely on, not for short term investment and “quarterly profit margins”, but for future generations to whom they would like to pass on the fishing tradition. The “fishing sector” understands better than anyone the dynamics involved with the caprices of the naturally fluctuating stock populations. Before the truncating of the fisheries through the faulty Transferable Quota System of catch shares, fishermen would logically switch gear and avoid a stock that was scarce that particular year—now they must fish for the particular species they were able to buy the quota or the “right” to fish for and land.

    The lessons that need to be learned are by the scientific and federal regulatory “sectors”. They need to learn that what is not “sustainable” is sensationalizing the “Boom and Bust” or natural cycles of certain species. This is often accomplished with self-serving spin that claims credit during an upswing (Boom), and issues dire warnings (and regulations) when a stock population is on the downside (Bust). This seems in order to propagate scientific papers and tenures, secure bureaucratic regulator’s funding (and jobs), and provide the sales pitch for the eco-NGOs harvesting of “donations”. In fact, that kind of chicanery by some in the academic/political/bureaucratic sector has balances in the ocean pretty screwed up as evidenced by the case of The Spiny Dogfish!

  2. I would like to support George Grachek’s comment that dogfish are not a high value catch. Currently in Delaware, for example, the price is frequently so low that fishermen don’t land them.
    In addition to the comments about competition, dogfish are predators. Often described as toothless, they do have teeth (don’t stick your fingers in their mouth)h post. Schooling dogfish bite chunks off other fish. In one sample of dogfish taken off North Carolina for a diet study, the most widespread item was chunks of striped bass. In the 2009 weakfish stock assessment, which I participated in, the hypothesis advanced in the assessment was that a combination of predation by striped bass and dogfish caused the large increase in natural mortality that caused the steep decline in weakfish. In New England waters, the NMFS diet sample collection shows they eat yellowtail flounder, and along with seals, the large increase in abundance of dogfish are prime suspects in the large increase in natural mortality exhibited by yellowtail (despite the fact that recent assessments have claimed that M = 0.20).

    Note: this is the legend for a chart that I tried to include.Catch-per-trip index of relative abundance of spiny dogfish from the MRIP along with the North East Fishery Science Center estimate of dogfish abundance.
    I will send a word file with the chart in case you think it could be included.

    1. Thank you for speaking up Desmond. One of the reasons that the ENGO/Govt./science sector can leave all this misleading information hanging out there in the public consciousness is because fishermen and scientists who know better don’t correct it.
      That is why this website is so vital and fishermen making common sense responses is so vital for the survival of these local small-boat, independent, family fishing operations— one of the last sources of nature-raised relatively uncontaminated food.

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