The threats to the planet’s shark populations are many and varied. They remained at the pinnacle of evolution – unchanged for millions of years – until superstitious and wasteful humans came along. Then things started changing for sharks, and not for the better. Today, they are demonized, stigmatized and hunted mercilessly – some to the point of extinction.
The benefits to the planet that shark populations provide are also many and varied. As apex predators, they play a pivotal role in controlling and regulating fish populations, and maintaining healthy and thriving marine ecosystems. It is easy to see that the meager short-term economic benefits of pulling sharks out of the sea pale in comparison to the necessary ecological value they actually have.
Sport-Fishing and Shark Derbies
“Jaws” hit the theaters in 1975. Almost immediately, western culture never wanted to go in the water again. And since then sharks have been vilified and scapegoated. The numbers, of course, tell a very different story. Five people were in the US during the three years from 1974 to 1976. The shark in “Jaws” killed five people (and one dog) in eleven days.
In fact, the global annual average of human fatalities from . In contrast, the global annual average of shark fatalities from unprovoked human attacks is somewhere between . Most scientists agree on a number around 100 million.
American sport-fishing kills about , which includes the seventy or so east coast shark derbies. Although they don’t account for a significant percentage of sharks being killed, the winning prize for any of these fishing competitions goes to the heaviest catch and only the largest of the selected species are targeted. This eventually turns an ocean of shark DNA into a wash basin.
Chinese Pseudo-Medicine and Shark Fin Soup
Jaws might have helped fuel the North Atlantic hatred of sharks, but across the Pacific they face a much graver threat than sport-fishing. Every year, the vast majority of the 100 million sharks we pull out of the sea are killed for their fins – which are of no nutritional value. Fins are cut off its body, and the shark is often still alive when it is thrown back to sink and drown at the bottom of the sea. What a way to go.
Shark fins are used in traditional Chinese pseudoscience and are believed to increase strength, stamina, virility, vitality and other such nonsense. The reality is that, as top predators, toxins from human industry in the food chain are concentrated in sharks, and eating them is doing nothing but harm – for everybody and everything.
Shark Fin Soup is also served by wealthy and vain Asian businessmen at social functions to display their affluence and impress their guests. Recently, things started slowly changing in China, due in large part to conservation campaigns like the one spearheaded by NBA star . One of the results of this campaign is that Shark Fin Soup is no longer served at official state functions. But, although Chinese consumption of Shark Fin Soup has been declining, .
This wasteful consumption also crosses oceans. Despite , Shark Fin Soup made from threatened species can be found in Chinese restaurants as far away as . Whenever we feel like some Chinese food, we’re always sure to ask if they serve Shark Fin Soup. Often, an affirmative answer is dishearteningly enthusiastic, in hopes we might order such a premium “delicacy”. We explain that we prefer to see our sharks in the ocean rather than on a menu, and why we’re eating somewhere else instead.
The US and are also considering a similar ban. argues that a US ban on the shark fin trade would do more harm than good for sharks. This, of course, is absurd. The authors of the study seem to make somewhat compelling arguments to sway the layperson’s opinion. However, debunks and discredits these arguments handily, and “demonstrate(s) that the figures used in support of this claim are inappropriately selected, misinterpreted or incorrect, and that therefore the argument cannot stand. In the face of the extreme depletion of shark numbers globally, the paper fails to give an accurate or objective assessment of the situation.”
Back in Hollywood, a version of “Jaws” called “The Meg” was recently released, where a massive prehistoric shark (Megalodon), terrorizes Chinese beach-goers rather than American ones. Apparently, has a slight environmental message with a couple of references to the destructiveness of shark-finning and plastic waste in the ocean. But, it didn’t have nearly the audience that “Jaws” did, and the dog lived.
Bycatch and Non-Targeted Species
Over 40% of the world’s fisheries () is bycatch, or non-targeted species. Sharks and fishing boats both tend to gather where there are fish, so it is hardly surprising that . The two biggest culprits are gill-nets and longlines. Gill-nets are spread across a stretch of sea and trap everything passing by, and fishing boats trail thousands of indiscriminate hooks for miles on longlines.
Accurate numbers of shark bycatch are almost impossible to determine based on reports from conflicting interests. However, none of the numbers include sharks that are thrown back in the sea still alive, only to die shortly thereafter. In some cases post-release mortality numbers are estimated to be equal to the number of sharks hauled aboard already dead.
Healthy Oceans and Greenhouse Gases
They are the ocean’s apex predators and shark populations are good indicators of a marine ecosystem’s health. Lots of sharks means a healthy ocean. To gauge the ocean’s health through this lens, consider that global shark populations have plummeted in the past fifty years. From the , to the , to the , their numbers have declined by as much as 90%. But, there are places on the planet bucking this trend.
Mexico’s Cabo Pulmo on the Baja Peninsula is an overwhelming success story and a testament to Nature’s ability to rebound when given a chance. In 1995, under pressure from the local fishing community, the Mexican government protected the area as a national marine park, and ten years later it was declared a UNESCO World Heritage site. Fifteen years after the fishing boats were evicted from the area, – more than any other Marine Protected Area in the world! Towering schools of thousands of jacks, Bull Sharks, barracuda, and massive stingrays among thousands of other species are now commonly seen by visiting scuba divers.
We have dived at Cabo Pulmo several times. The last time we were there, the main bay was blown out by strong northerly winds, so we were relegated to the south side of the marine park around the headland. Although the park encompasses the headland, the rest of the Los Frailes beach to the south is fair game, and fish camps are set up just outside the park boundary. In our two dives there all we saw was a stingray without a tail. The difference between the main protected area and the bay just around the corner to the south was astounding.
Perhaps the greatest global threat of the ocean losing its apex predators is the effect on carbon dioxide levels. Like us, fish and zooplankton (ie. marine biomass) breathe oxygen and exhale carbon dioxide. Sharks eat fish that eat smaller fish which eat zooplankton that eat phytoplankton – algae which coverts CO2 into oxygen through photosynthesis.
concluded that fewer sharks means more breathing marine biomass, and more breathing marine biomass means more CO2. Fewer predators also means more fish dying and sinking to the bottom of the sea, where they decompose and release CO2 instead of feeding the food chain. As one might expect, when the top of the food chain is gone, the bottom won’t be far behind. A decrease in sharks means an increase of small fish and zooplankton, which prey on the phytoplankton – the algae that converts CO2 into oxygen.
Shark Tourism vs. Shark Fishing
Shark tourism is any activity that involves watching live sharks in their natural habitat without killing them. Shark tourism is NOT visiting aquariums with captive sharks or buying souvenirs made from sharks, which include teeth and jaws.
Around the world, reports examining the economic value of sharks often surface and always draw the same conclusion: a shark is worth more alive than dead. If we look at , the economic impact of shark diving was nearly $400 million and supported almost 4000 jobs in 2016. In contrast, shark fin exports from the entire US in 2015 was , and Florida’s entire shark fishery brought in less than that. The math is pretty simple.
In the nearby , shark and ray tourism brings in over $115 million every year and accounts for 1.3% of that country’s entire GDP. By comparison, agriculture makes up 2.3%. Meanwhile, in shark tourism brings in $18M – a whopping 8% of it GDP. Similar economic benefits of shark diving is documented in every ocean. Direct consumer expenditures on shark diving from other significant Indo-Pacific destinations include: , and the . The small community of Semporna on Borneo, Malaysia’s most popular diving destination, enjoyed in 2012.
The total revenue brought by shark tourists (transportation, accommodation, food, etc) is several times greater than direct diving expenditures. And, if it wasn’t for shark tourism, , if they saw any at all. Back in Cabo Pulmo, tourism businesses report revenues that allow them to pay employees double the Mexican average and definitely more than the fishermen around the corner make.
Like all human activity, shark diving alters animal behavior. A 2018 study found that the presence of cage-divers . Sharks are attracted to the boat by a chum line and lured to he cage with tuna heads tied to a rope. Sometimes, the shark gets hold of the bait for a free bite.
Shark-feeding dives alter a shark’s behavior to a greater degree by teaching sharks to associate humans (or at least divers) with food. Nonetheless, the sharks are not captive or killed, and are still making money. Additionally, there is no scientific evidence to support claims that shark diving increases the risk of an attack on a human.
Although the international trade of shark products declined by , in 2013 the global shark fishery was still worth twice that of shark tourism. But, shark fisheries have been declining steadily for 20 years, while shark tourism is exploding exponentially. to $700 million in the next 15 years, provided there are any sharks left to see. In many cases, shark fishing revenues are a fraction of the as a result of that fishing. If we fish them out, both industries will collapse, as will the oceans and, in turn, our planet.
Convention on International Trade of Endangered Species
Fortunately, positive regulatory changes for several shark species have been implemented over the past twenty years. In 2000, the (CITES) moved Great White, Porbeagle, Scalloped Hammerhead and Basking Sharks to Appendix II, which lists them as “species that are not necessarily now threatened with extinction but that may become so unless trade is closely controlled.”
Although all shark populations have suffered a steep decline during that same time, and our planet’s average temperatures continue rising, the only sharks on Appendix I (threatened with extinction and international trade is prohibited) are Sawfishes. Of the more than 400 shark species out there, only a couple dozen are listed under CITES. All the other species are fair game for sport-fisherman and shark-finners.
. But, shark populations have an average rebound rate (sustainable fishery) of only 4.9%. Again, simple algebra exposes the unsustainable nature of this depletion. They are the fastest swimmers in the sea, but sharks are also pretty slow fish and cannot keep up to the pressures they face. They grow slowly, and more importantly, reproduce slowly. This means that when they are fished to such extremes, the volume of reproductive stock is exponentially reduced, thereby making a population rebound impossible – regardless of efforts, political or otherwise.
CITES is great place to start, but the only real solution is for every country to ban the sale and import of shark fins. Unless all jurisdictions work together, the shark-fin market simply shifts to somewhere without such regulations. Stiffer penalties, including vessel seizure and substantial jail-time for the culprits, are required to enforce global shark protection laws.
Given the stats and facts, it amazes us that we see any sharks at all when we go diving, and encountering one always makes us feel lucky. To increase our chances of seeing sharks, we do what we can to do help protect them and spread the word of their plight.
“I see the sea today from a new perspective, not as an antagonist but as an ally,
rife less with menace than with mystery and wonder. And I know I am not alone.
Scientists, swimmers, scuba divers, snorkelers, and sailors all are learning that
the sea is worthy more of respect and protection than of fear and exploitation.”
– Peter Benchley (“Jaws” author)
What can you do to help?
- Don’t eat fish. The more commercially-harvested seafood we consume, the more sharks will be killed as bycatch.
- Don’t give places that sell shark products your business, and let them know why you’re spending your money elsewhere.
- Give places that don’t sell shark products your business, and let them know why you’re spending your money there.
- Contact your elected officials at all levels of government, and urge them to introduce or support legislation that bans the sale and import of shark fins.
- Tell everyone you know about the threats to our ocean’s sharks, and what they can do to help save these majestic creatures.