Two iconic shark species — oceanic whitetip and scalloped hammerhead — as well as many other sharks and rays inhabiting the open ocean are being pushed toward extinction. Main threat? Overfishing. How did we get here and what can be done to save them?
by Dr. Andy Cornish, WWF Global Shark Leader
You don’t forget your first time underwater with a school of scalloped hammerheads. The undulating way they swim together is a thing of beauty. I had travelled all the way to Mozambique to be surrounded by these predators, and was in awe. Years later, in the Red Sea, I had the same thrill at the sight of a hefty oceanic whitetip inspecting me close up. Seeing these majestic animals underwater is one of the best wildlife experiences anyone can have.
But we’re emptying our oceans of these fantastic creatures at a scale that is breathtaking. Globally, oceanic shark and ray populations have declined by 71% since 1970, with species such as the oceanic whitetip and scalloped hammerhead declining by over 95% and 80% respectively. The whitetip used to be the most common shark species in the open ocean. Yet today there are only a handful of locations where divers have a decent chance of seeing them.
The oceanic whitetip, as its name suggests, is mostly found in the open ocean or near distant islands.
Scalloped hammerhead sharks are born in shallow coastal waters, and move to deeper offshore waters later in life. With these two species spending so much of their lives far away from land, you might think they would be safer from humans. But regardless of how far these animals go, there is no escape from their biggest threat — overfishing.
Sharks eat fish. So it’s no surprise that where you find schools of tuna, marlin and other open ocean fish that people eat, you will also find sharks and rays. Sharks are killed — as many as 100 million every year — both on purpose and incidentally by fishing vessels targeting an array of species. But how did the carnage get so bad?
The way we catch tuna is a big part of the problem. While the mechanization of fishing started in the late 19th century, it was not until the 1950s and 1960s when the gear and the size of the boats would enable rapid intensification of industrial tuna fishing. In the 1970s it was already apparent that the ocean’s resources were not, in fact, infinite and fish stocks could collapse if not looked after responsibly. But knowing and changing don’t always go together. By 1985, global fishing catch numbers exploded, quadrupling since the end of World War II.
Fast forward to the early 21st century and the situation could not be more alarming. Fishing effort with longlines and purse seine nets — two tuna fishing methods that result in high shark catches — has more than doubled since 1970, resulting in an 18-fold increase in relative fishing pressure. Meanwhile, catches of oceanic sharks and rays have tripled in the same time. 1990 marked a critical point in this timeline of destruction: shark and ray catches massively increased to meet new market demand for their products — in particular fins. Catches continued climbing steeply until early 2000s, and then, in a tell-tale sign of overfishing, they started to drop simply because there were fewer animals left out there.
In addition to the oceanic whitetip shark and the scalloped hammerhead, there are 22 other species of oceanic sharks as well as rays that are now threatened with extinction. 16 of those are now endangered or critically endangered. These animals occupy diverse habitats and have different migration patterns, but all have been ravaged by unsustainable fishing. The truth is there is no place for them to hide, even in the vast, open ocean.
But this is a human-caused problem, and it’s in our power to fix.
Tuna fishing on the high seas — beyond the national jurisdiction of any particular country — is regulated by regional fisheries management organizations (RFMOs). While most people have never heard of these tuna RFMOs, they govern unimaginably large swathes of our blue planet. The Western and Central Pacific Fisheries Commission (WCPFC), for example, manages an area covering 20% of the Earth’s surface — more than the size of Russia and Canada combined!
A good idea in principle, tuna RFMOs are marred by a number of ongoing issues. Members, or “contracting parties” (nearby coastal countries and any other countries fishing in those areas) gather just once a year for a major meeting when all key decisions for the following year should be made. But a requirement that any decision is made by consensus means it is enough for one contracting party to object to a proposal for it to be shelved. In practice, this means tuna RFMOs are slow to act on overfishing issues, let alone change course drastically.
With RFMOs’ mission to manage tuna fishing, other species — including sharks and rays — rarely get the attention they deserve. In 2019, after shocking population declines of the oceanic whitetip shark in the Pacific came to light at the Western and Central Pacific Fisheries Commission (WCPFC) meeting, WWF called for countries to develop recovery plans. The issue was never even discussed. Pushed to the end of the agenda, it seems there’s never enough time to address the plight of sharks and rays.
Another often-cited reason for lack of action is “insufficient scientific data” on what is being caught — this could be easily fixed, except the political will is lacking. Countries refuse to increase on-board scientific observers from the current requirement of a paltry 5% of tuna fishing vessels, so is it any wonder we lack data from fishing boats that spend months at sea with nobody watching? Is it any wonder that sharks and rays have been decimated when there are no catch limits for them?
But I refuse to lose hope. So many marine species can bounce back if we take the pressure off. The smooth hammerhead, for example, is slowly recovering in the Atlantic thanks to the management measures that were implemented to counter earlier steep declines.
To prevent extinctions and help recover these majestic creatures, WWF is urging all tuna fishing states to implement a set of urgent, science-based measures to recover oceanic sharks and rays. High on the list: 100% observer coverage on all industrial fishing vessels by 2030 to collect data, monitor catches, and prevent any illegal, unreported, and unregulated fishing. Also needed: recovery plans for all critically endangered oceanic sharks and rays by 2023, and all the endangered ones by 2026.
The dramatic plight of these iconic marine predators demands drastic actions from the countries that fish them. The alternative would be a devastating blow to the health of our ocean, and to the wonder and awe we experience from sharing this blue planet with sharks and rays.