A Third of All Sharks and Rays Are Now Staring Down Extinction
A new study finds roughly a third of sharks, rays and chimaeras are threatened with extinction, mostly from decades of overfishing.
A study out today puts a hard number on something marine biologists have been warning about for years: roughly one-third of all chondrichthyes species — that’s sharks, rays, and their less-famous cousins the chimaeras — are now threatened with extinction. The primary driver isn’t habitat loss or climate change, at least not yet. It’s overfishing, plain and simple.
That’s a strange thing to sit with. Sharks occupy this weird cultural space where they’re simultaneously feared as apex predators and, it turns out, deeply vulnerable to us. They’ve been around in some form for over 400 million years, surviving multiple mass extinctions, and in the span of a few human generations we’ve managed to put a third of them on the ropes.
The researchers behind the study say the decline has accelerated sharply over the past 50 years, tracking almost exactly with the growth in global demand for shark fins and meat. Shark fin soup is the poster child here — it’s been a driver of targeted shark fishing for decades — but it’s not the whole story. A lot of the mortality is incidental: rays and smaller shark species caught as bycatch in industrial fishing operations aimed at completely different fish, then discarded or sold off as a secondary product because, well, the boat’s already out there.
Rays in particular don’t get the press that sharks do, but they’re arguably in a tougher spot. Many ray species are slow to mature and have very low reproductive rates — some give birth to just a handful of pups every couple of years. That biology worked fine for hundreds of millions of years in the absence of industrial-scale fishing pressure. It does not work fine against modern trawling fleets.
The obvious policy response is stronger international fishing regulation, and that’s exactly what the researchers are calling for — tighter catch limits, better enforcement of existing shark-finning bans, and more protected zones in international waters, which is where a lot of chondrichthyes population loss is happening precisely because no single country’s laws apply. CITES, the international treaty governing trade in endangered species, has slowly been adding shark and ray species to its protected lists over the past decade, but enforcement at ports and on the water remains spotty at best.
There’s also a knock-on ecological argument that doesn’t get made often enough: sharks and rays sit near the top of a lot of marine food webs, and losing them at this scale isn’t a contained problem. Apex and mid-level predators keep populations of smaller fish and invertebrates in check; pull a third of that layer out of the ocean and the ripple effects show up in fisheries and ecosystems that seem, on the surface, to have nothing to do with sharks.
None of this is an unsolvable problem — fin-ban enforcement and catch-limit reform have measurably helped specific populations recover before. But it requires the kind of coordinated, boring, unglamorous international regulatory work that rarely gets headlines the way a great white sighting does. Today’s numbers are a reminder that the unglamorous work is exactly what’s needed, and that the clock on it is running faster than most people realize.