Five pairs of rubbery feet carry velvet-sheathed black-and-white bodies towards the rope line separating the king penguins from the dozen or so visitors, who look on in awe. As these emissaries shuffle over, a hundred of their cohorts parade on a nearby bank, splashing around in the water and regurgitating food into their chicks’ open beaks.

The king penguin (Aptenodytes patagonicus) makes its home almost exclusively on islands in the Southern Ocean. But it has been coming to this wind-battered bay in southern Chile’s Tierra del Fuego region for hundreds of years, probably because its shallow shores offer protection from marine predators and humans.

Early explorers named it Useless Bay because those same shores made landing boats, including industrial fishing vessels, nearly impossible. Still, humans remained such a threat that no permanent colony of king penguins formed here until 2010. Then, as a colony started to develop, a local landowner and former kindergarten teacher Cecilia Durán Gafo, now 72, decided she would protect them.

Today, she runs a reserve that oversees the only continental king penguin colony in the world, one that has grown from a handful of penguins to nearly 200.

“It was only thanks to the reserve that [the penguins] got a safe space where they could build up and establish a colony,” says Dr Klemens Pütz, scientific director at the Antarctic Research Trust.

Durán’s reserve is part of a growing global trend. A 2022 study in Nature Ecology and Evolution, assessing more than 15,000 private protected areas, found they helped to conserve underrepresented biomes and highly threatened regions that government action alone could not reach.

The first time Durán found king penguins nesting on her land was in the early 1990s. But soon after, she says, people claiming to be scientists arrived to take the birds away.

“They put [the penguins] in cages, and took them to Japan … supposedly for scientific research. Later, we found out [most] had gone to zoos [or homes] as pets,” Durán says.

After that, the penguins avoided settling in the bay for more than a decade. And when they reappeared overnight in 2010, Durán says, people began stealing eggs and mistreating them again almost immediately. “They dressed them up in caps and sunglasses, and took selfies,” she recalls. “Horrible things.”

The population quickly collapsed. Of the 90 king penguins, only eight remained a year later.

Durán called a family meeting, convinced they had to do something to protect the penguins. “But who was going to do it? ‘Mom! my two daughters said in unison.’”

So she began patrolling the beach. “Every day I came out here with a thermos and a sandwich. I’d spend the whole day, frozen to the bone … making sure people didn’t disturb the penguins.”

The next year, Durán fenced off 30 hectares (74 acres) of her nearly 1,000-hectare farm as a protected area, allowing visitors to watch the penguins, but only from a distance.

Keeping humans out was only half the battle, though. Minks and grey foxes, invasive species introduced to Tierra del Fuego in the 20th century, posed a novel threat to the penguins, which have no natural land predators.

“The mink doesn’t attack the adults, but goes for the chicks and the eggs. At first, only one or two penguin chicks survived. Then we started our years-long battle,” says Durán.

For the first decade, Durán’s solution was simple: lure the predators away, especially in winter, when adult penguins forage at sea for weeks at a time, leaving the chicks unprotected.

By then, she had a small team. They would buy offcuts from local butchers, split the night into two-hour shifts, and distribute meat scraps far from the reserve, conditioning the predators to hunt elsewhere.

“It was wonderful because the nights were so full of stars, but the 3am shift, oof,” she remembers. “I went out anyway.”

They also started using dogs. “They go out in the morning and afternoon [to mark the territory] … So the fox or the mink smells it and leaves,” Durán says.

Over time, the reserve also became more professional. In 2011, Durán started the process of legally turning the 30 hectares into a reserve for the next 100 years. “Whoever inherits has to continue the conservation project,” she says.

Her 12-person onsite team now includes biologists, veterinarians and ecotourism specialists. Ecotourism funds the operation, with an average of 15,000 visitors a year.

The team also regularly collaborates with universities to contribute to scientific penguin, bird and plant life research. Data collected has revealed that king penguins from colonies thousands of kilometres away are coming to the bay. These new arrivals immediately adapt to the local diet, in what scientists call “exceptional foraging plasticity”.

The finding is significant: that plasticity “could hopefully help them to survive major human-driven climate impacts”, says Pütz, the study’s lead author.

Meanwhile, Durán is seeing evidence that her approach is paying off, with more chicks fledging as the most tangible result. “Last year, 23 chicks survived – a record,” she says.

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