How Many Sharks Are Killed Each Year?
Although the exact numbers of sharks killed are difficult to estimate, a number of studies have drawn attention to the alarming volume of sharks overfished and killed solely for their fins worldwide, each year.
The first scientific published by Clarke et. al. (2006), who estimated estimate of 73 million sharks, on average, killed annually for their fins. The finding was based on an analysis of shark fin inventory in the Hong Kong dried shark fin trade. This was about three times more than the official catch number reported to the United Nations at the time.
The most recent estimate of sharks killed each year was published by Worm et. al. (2024), estimating that shark fishing mortality increased from 76 million to 80 million sharks per year during the study period. This is despite the ten fold increase in protective legislation to reduce finning over the same period. More than 30% of this catch was for species currently threatened with extinction. When also accounting for sharks not properly identified by species, the global mortality estimate rose to 101 million sharks in 2019 according to the authors.
Based on an analysis of shark weights from landings data, an earlier study by Worm estimated global shark mortality at about 100 million sharks in 2000, and about 97 million sharks in 2010, with a total
range of possible values between 63 and 273 million sharks per year.
Shark populations have declined significantly as shark effort has increased 18 times, yet the demand for shark fins continues to drive overfishing. Tens of millions more sharks and rays are killed each year than accounted for, primarily through illegal, unregulated and unreported fishing (IUU). As a result of overfishing, over 300 shark and ray species are Red listed as vulnerable, endangered, or critically endangered by the International Union for the Conservation of Nature (IUCN).
Although focus by many conservation organizations has been on finning, the problem lies in overfishing in directed fisheries such as the blue shark fishery, and as bycatch in tuna and swordfish fisheries. Although more shark bodies are retained, much of the financial incentive is driven by the shark fin trade.
Shark finning is a fishing practice where sharks are caught and their fins are sliced off, then the body of the shark is discarded, alive or dead. Shark fins are particularly sought after for traditional Chinese medicine and shark fin soup which is considered a delicacy in Asia. Catalyzed by the shark fin trade, large shark populations are declining globally, and many species are imminently threatened with extinction.
What is Shark Finning ?
Shark finning is the practice of removing the fins from a captured shark, and discarding the animal at sea, still living or dead. This reprehensible and wasteful act is largely driven by the high value placed ion the fin, and the low value off shark meat. Sharks captured as bycatch- (an untargeted animal)- in the tuna and swordfish industry that were once released, are now increasingly killed for the fins. The high value and increased market for shark fins is creating huge incentive for fishermen to take the fins and discard the animal, leaving room in the ship’s hold for the more valuable meat of the tuna or swordfish. Shark finning is wasteful, inhumane and unsustainable. The shark fin trade however is supported by illegal and legal fisheries alike.
Is Shark Finning Illegal?
Since 2000 several countries including the United States have adopted laws within their waters and the high seas to ban this practice. A few, such as the United States and Australia, have successfully enforced these laws where vessels have fins without the sharks, or where fins are not naturally attached. Some countries allow a ratio of fins to bodies at around 5% fin to 95% body ratio. This can lead to a misrepresentation of species captured, smuggling of fins from endangered or protected sharks, and can allow for more sharks killed than actually reported. The ICCAT and the West PAC Regional Fisheries Management Organizations (UN designated member commissions of Atlantic and Pacific pelagic fisheries) have banned shark finning in their tuna and swordfish longline fleets. This is a good start but difficult to enforce against smugglers or poachers. However, the fisheries managers in the Atlantic have failed to close the loophole of requiring sharks landed with their fins naturally attached. Restricted in the Pacific Ocean, this loophole allows fishermen to land their sharks and fins separately with a ratio of fins to carcasses. This loophole make enforcement of shark finning challenging, and allows for more sharks to be killed, including protected species, than are accounted for.
Although over 300 species are listed by the IUCN as endangered or threatened, only around 100 species are protected from the fin trade by the Convention on International Trade in Endangered Species of Fauna and Flora (CITES). However, small boats and nations who do not recognize CITES or other treaties are actively shark finning and trading with impunity. The best solution to save sharks will rely on national and international efforts to regulate fisheries, enforce laws against Illegal Unregulated or Unreported (IUU) fishing and regulate the shark fin trade.
Can Shark Fins be Sold Legally?
The shark fin trade is global and widespread. In the USA. The import/export and sale of fins in the USA is illegal as of December 2023, joining Canada and the UK as the only countries that ban the shark fin trade. Countries that do not have shark finning bans including China, India and Indonesia. Currently there are very few regulations on the sale of shark fins globally. Shark fins can be sold legally in countries with anti- finning regulations, yet the source of the fin and method killed can still be illegal. These agreements require the shark carcass to arrive at the dock with the shark, or if severed, on an agreed fin to body ratio. In some regions like the EU, this ratio is so high that it allows more sharks to be captured than reported by the actual fin weight. Most shark fins go to Hong Kong for processing, and re-exported to China and other countries like the US. Fins traded as a dried product do not have any documentation of where that shark was captured, the species or if it was legally harvested or finned on the high seas. Most shark fins are virtually unrecognizable by species. Once it is in the market or in the bowl, most consumers will not know where the fin came from, or if it was harvested legally or illegally.
What Sharks are killed for their fins?
Any shark is fair game, but some species are more prized than others. The large fins of Whale Sharks, Basking Sharks are coveted for decoration at restaurants. These species are among the most threatened. Pelagic species such as Oceanic White tip and Silky sharks are common in the high-end trade. Illegal fisheries such as those that target the Galapagos, Cocos Island reserve and other remote islands capture reef sharks and hammerhead sharks. The Blue shark is among the most common shark killed and traded with an estimated 20 million killed for their fins annually.
By nature, sharks are difficult to study and good fisheries data are hard to obtain. The practice of finning, which is mostly an unreported practice is robbing scientists of population and capture data. Many pelagic shark species are widespread and do not school. Many larger sharks travel vast distances alone. Most large sharks have late onset of fertility (decades) give birth to few young and have long gestation periods, making them very vulnerable to overfishing. Therefore, it is very difficult to arrive at a sustainable number. This is why most commercial shark fisheries collapse economically.
With accurate population numbers, a good understanding of the target shark’s biology, and accurate reporting of animals captured, a sustainable fishery might be achieved. Until that is achieved and it can be enforced, then the source of fins must stop and fins made illegal.
What Sharks are Protected or Most at Risk?
The International Union for Conservation of Nature has designated Red List status of threatened, endangered or critically endangered to 316 species of sharks. A 2021 evaluation by Dulvey et al finds that over 37% of sharks, rays and skates are threatened with extinction. These include Manta Rays, Whale Sharks, Hammerhead Sharks and Oceanic Whitetip Sharks. A 2004 study by Baum and Myers suggests that 90% of many large species have been overfished.
The United Nations Convention on the Trade of Endangered Species of Flora and Fauna (CITES) lists species of concern and threatened with extinction. Only the sawfishes Sawfishes (Pristidae spp., 7 species) are protected under Appendix I of CITES- inferring complete protection from commerce. CITES listed Whale shark (Rhincodon typus) shark, Basking shark (Cetorhinus maximus) and Great white shark (Carcharodon carcharias) under Appendix II in 2003. Oceanic whitetip shark (Carcharhinus longimanus) Porbeagle shark (Lamna nasus) Scalloped hammerhead shark (Sphyrna lewini) Smooth hammerhead shark (Sphyrna zygaena) Great hammerhead shark(Sphyrna mokarran) Manta rays (Manta spp.) were added in 2013. In 2016 Silky shark Carcharhinus falciformis, Thresher sharks Alopias spp. and Devil rays Mobula spp. were added in Appendix II. In 2023 nearly 100 species were added to Appendix II listing including all members of the families the guitarfish (Rhinobatidae), the requiem sharks (Carcharhindae) and the hammehead family (Sphrynidae).
CITES regulates import, exports but does not protect living sharks.
Great white sharks are protected under California and Federal Law from fishing commercially or recreationally. Even,fins from these protected sharks have been identified in the shark fin trade through DNA analysis.These laws regulate the trade and transport of listed species across country lines by countries that recognize the treaty. To date,169 countries have agreed to be legally bound by CITES. Nearly twice as many nations had teams in the World Cup.
In 2006 investigators performed DNA testing on wholesale shark fin distributors, discovering the fins of the few protected species in Hong Kong, Singapore and here in the US. In 2010 Shark Stewards, working with at the California Academy of Sciences sequenced 17 species of sharks from shark fins bought in San Francisco Chinatown, including threatened species like thresher sharks, and endangered hammerhead sharks. Once the fin is dried and treated, the species is nearly unidentifiable. The protections in place are not strong enough, or broad enough to protect sharks.
How are Shark Fins Used?
Shark fins are used to make shark fin soup, a delicacy once prepared exclusively for the Chinese emperors and nobility. The cartilage from the fin is carefully dried and prepared, and used as an ingredient in a soup flavored with seafood or chicken broth and herbs. The process of preparation makes this dish very costly, as much as $100.00 a bowl, and is commonly served at banquets and weddings. The serving of the dish is considered very prestigious and even propitious.
Dried shark fin is the most expensive seafood product by weight, and is creating huge incentive for fishermen to hunt sharks, solely for their fins. Sold for upwards of $1,000 per kilogram ($2,200 per pound), dried shark fin is among the highest valued seafood by weight.
Who Eats Shark Fin Soup?
Although Chinese and people of Chinese descent primarily consume the dish, the consumption is increasing in western societies with affluent consumers, Asian and non-Asian.
Around 50% of the dried fin market is brokered through Hong Kong and China is the primary market for shark fin. However, shark fin is still a major trade and is consumed widely in the USA, putting shark populations at risk. According to the UN FAO, other countries reported exporting 600 metric tons of shark fins into the United States in 2011.
Shark Fin Soup is Associated with Asian Cultural Celebrations. Is This an Attack on Asian Culture?
This is an attack on an unsustainable fishing practice and trade. The cultural associations are modern, associated with prestige. The problem is simple economics: increasing affluence creates increased demand. This demand is exceeding the supply, which is creating a positive feedback loop, making the shark fins more difficult to obtain, and increasing the price, making the dish more expensive, increasing the prestige. This in turn motivates fishermen to obtain shark fins from a steadily diminishing source of sharks. Many countries have had practices associated with their cultures that were recognized as harmful or unethical and were stopped to protect wildlife.
Isn’t Shark Fin Soup Healthy?
Shark fin soup has been associated with a variety of benefits from increased virility to longer life. However, the fin is purely cartilage, the same compound in human, cow and other vertebrates. Cartilage has no nutritional value. Any benefit would come from the broth and other ingredients added. A 2012 study of fins from seven species of shark found a neurotoxin known as BMAA in 80 percent of 29 samples. A follow-up study in 2016 discovered BMAA in 87 percent of 55 fin and meat samples spanning 10 different species. BMAA may be a risk factor for several degenerative brain disorders including Alzheimer’s, Parkinson’s and Lou Gehrig’s disease, or ALS. The highest concentration of BMAA was detected in the fins.
Shark fins are also high in mercury, a known reproductive, developmental toxin and one that can cause permanent nerve and brain damage. The process of treating and drying shark fins can actually concentrate mercury and make the levels higher. The US FDA recommends that pregnant and breastfeeding women and children avoid eating sharks, swordfish and certain kinds of tuna. Fetuses, infants and children are at particular risk because their developing brains are more sensitive to disruptions from mercury and other neurotoxins.
The World Health Organization has tested shark fins and determined some fins to be so high that one bowl of soup would exceed the recommended exposure. Shark Stewards has similarly tested fins for soup and determined that people who consume shark fin soup even occasionally are at risk to high mercury levels.
Importance to Ocean Health
As apex predators, large sharks like great white sharks play an important role at the top of the marine food chain. Removing these top predators creates an imbalance called a trophic cascade leading to less abundnace and declining ecosystem health. Without them, the entire food chain can be affected, negatively impacting the entire ecosystem, including fish humans love to eat.
Vulnerability
Large shark populations are plummeting due to overfishing and the shark fin trade. In general this group of fish is slow growing, late maturing, and produce few young compared to other fishes. These characteristics make them especially vulnerable to exploitation by humans.
SOURCES
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