Getting out of the ocean after a scuba dive in Patagonia Azul, Lucas Beltramino realised there was an unexpected passenger on his boat.

“We were carrying out a project looking at the experimental restoration of algae,” Beltramino tells me. “After the session, while I was taking off my equipment, I saw that a stowaway had boarded with me: a small octopus. I geared up again and got back into the water with the octopus.

“When I got to the bottom, I opened my hand to let the octopus go. The first thing it did was to swim back to my hand. It was incredible. I released it again – it hid behind the algae and spied back at me.”

Octopus are just one of the remarkable creatures that live in Patagonia Azul, off Chubut Province in southwest Argentina. An area of 7.7 million acres, it was declared by UNESCO as the Patagonia Azul Biosphere Reserve in 2015, with 58% of the area marine and the remaining 42% terrestrial.

This coastal-marine zone, between the cities of Comodoro Rivadavia and Rawson, is home to more than 60 protected islands and bays that serve as feeding, breeding and nesting grounds for numerous species of birds and marine mammals, from sea lions, whales, orcas, dolphins and sharks to Magellanic penguins and the endangered, endemic Chubut steamer duck.

It also has abundant and diverse algae meadows and kelp forests, which are vital to the health of the marine ecosystems. The area has the greatest biodiversity found anywhere on the Argentine coastline. And Lucas Beltramino, Conservation Coordinator for Rewilding Argentina’s Patagonia Azul project, is one of the people working to keep it that way.

“Patagonia Azul and specifically the areas near the town of Camarones are very different from the rest of the Argentine coast,” Beltramino explains. “There is a food web that makes this area so productive. The islands are also an ideal place for birds and marine mammals to reproduce, far from continental predators. That’s why this area is so important.”