While anglers cannot take endangered sand tiger sharks, a loophole lets private firms catch the fish to sell abroad, profiting from Delaware Bay’s conservation success

Shortly after 12.45pm, what remains of a 300-metre line goes taut. Somewhere beneath the murky green surface of Delaware Bay, on the eastern US coast, a sand tiger shark has taken the bait of a mackerel chunk. Marine researchers at the University of Delaware haul the line towards a small boat as the shark’s grey-brown outline emerges.

It is a large animal: 225cm (7ft) long with a 90cm girth. Its mouth hangs open, revealing rows of jagged teeth. The researchers work quickly, measuring the shark, recording its sex, and taking blood and muscle samples. A tag is then fastened beneath its dorsal fin, through its thick sandpapery skin.

Peru’s anchoveta have made up about a 10th of the entire global commercial fishing catch since 1970, more than any other fish. A combination of warming seas and decades-long overfishing spells disaster

On 10 June 2026, the government of Peru made a decision that it knew would hurt one of the world’s major fishing industries. It stopped all anchoveta fishing boats from going out to sea, suspending the fishing season. At first the order was temporary, but in mid-August, the suspension turned into a total closure. This was no easy call. For one thing, it was a brutal blow to the Peruvian economy.

Peruvian anchovies – the scientific name is Engraulis ringens – are not the salty, punch-packing little fillets in a puttanesca sauce or caesar salad dressing. That is a different species – Engraulis encrasicolus – which is smaller, tastier and found mostly in the eastern Atlantic and the Mediterranean. Only a small part of Peru’s anchoveta catch is eaten in fish form. The rest – more than 90% – is immediately processed as fishmeal and fish oil, packed in sacks and barrels, and shipped to fish, shellfish and seaweed farms, factory farms and nutritional supplement producers around the world.