In this week’s newsletter: the archipelago at the centre of the extreme weather phenomenon could help scientists predict how other marine ecosystems will adapt to our warming climate

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The ocean waters around the Galápagos Islands are hot. Very hot. Observed for centuries in the Pacific by fishers, the El Niño weather phenomenon begins when the prevailing trade winds slow, allowing warm water to spread east along the coast of South America. Right now, the pattern is in full flow and will build from this year into next, likely bringing record temperatures to an already overheating world.

If 2026 is not the hottest year on record, 2027 surely will be – and the Galápagos archipelago is in the centre of this climate crisis.

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While most visitors prefer the finches, tropicbirds and blue-footed boobies, some are drawn to less glamorous species

Most visitors don’t come to the Galápagos for the gulls. With more than a dozen kinds of Darwin’s finches on offer – along with fearsome frigatebirds, ethereal tropicbirds, and comical blue-footed boobies – my tour companions could be forgiven for overlooking these less glamorous seabirds.

But as a lifelong laridophile (as gull enthusiasts are known), I had two particular target species here. And on our first day’s sailing, as we landed on North Seymour Island, I saw my first: a large gull with a dark grey head and strikingly zigzag-patterned wings.

The species is abundant within the protected archipelago but when they migrate outside the marine reserve to give birth they run the gauntlet of industrial fishing

The unmistakable fluted T-shape of a scalloped hammerhead shark slides by, followed by a diver holding his breath and a metal spear like an extra-long snooker cue. The spear hits the fish behind its dorsal fin and the 2-metre shark darts away, disgruntled but otherwise unharmed.

Carlos Robalino, a marine biologist from the Galápagos Islands, trained as a shark researcher in Mexico but is now back home and working as a junior researcher at the Charles Darwin Foundation. When we meet in March, he is one of the divers on the foundation’s research expedition to Darwin and Wolf, the most northerly islands in the Galápagos marine reserve.

Subspecies driven to extinction by hungry whalers returns after ‘back breeding’ programme using partial descendants

Giant tortoises, the life-giving engineers of remote small island ecosystems, are plodding over the Galápagos island of Floreana for the first time in more than 180 years.

The Floreana giant tortoise (Chelonoidis niger niger), a subspecies of the giant tortoise once found across the Galápagos, was driven to extinction in the 1840s by whalers who removed thousands from the volcanic island to provide a living larder during their hunting voyages.