It is a perfect autumn day for a clifftop walk: sea and sky blend into a veil of baby blue, and the water is calm and dazzling. A motorboat unzips the ocean as we\u00a0squint out over the bay.<\/p>\n
My companion points to a dark line snaking along in the water. It seems to intensify for a moment, then erupts in a silver commotion. Through binoculars I can make out\u00a0the frantic leaping of a shoal of eel-like fish. \u201cGarfish<\/a>,\u201d he says. \u201cNow just watch.\u201d<\/p>\n Suddenly, the water erupts as a monster bursts into the air, scattering the garfish like sequins. Dark on top, with fins like daggers, its silver underside is lit up by the sun, massive as a billboard caught in headlights. It crashes down, swallowed up by its own whirlpool. Another leaps, and another. Tuna!<\/p>\n Atlantic bluefin tuna chasing garfish off the Devon coast. Photograph: Ray Harrington\/Devon Sea Safaris<\/p>\n By the time I\u2019ve remembered to breathe again, the surface of the water is still and twinkling once more, as if I\u2019d hallucinated the whole thing. Atlantic bluefin tuna (Thunnus thynnus<\/a>) have, as I\u2019ve just found, made an astonishing return to British waters. And what astonishing animals they are \u2013 they can live up to 50 years, grow to 3\u00a0metres and reach speeds of more\u00a0than 40mph. This apex predator hunts in packs, herding its prey to the surface. I\u2019m glad I\u2019m\u00a0not a garfish.<\/p>\n A common sight off England\u2019s south coast until the 1950s, overfishing then pushed them almost to extinction here. In the early 2000s, strict regulations were introduced \u2013 and the results are clear to see<\/a>. This shows \u201cthe power of effective management\u201d, as Chris Graham of the Marine Conservation Society<\/a> puts it.<\/p>\n But Chris also identifies the \u201cbackground issue\u201d of global warming, which is changing the migration patterns of tuna and their prey. Bluefin tuna need warm water and, after this year\u2019s heatwaves, the Devon coast must be like heaven.<\/p>\n The multiple catastrophic effects of the climate crisis on ecosystems are \u2026 well, too horrific to look at head-on. So let\u2019s focus, if only for today, on this astonishing good news story. In 2021, Atlantic bluefin tuna were reclassified on the IUCN red list from \u201ccritically endangered\u201d to \u201cleast concern\u201d. It\u2019s a giant leap.<\/p>\n