Editor’s Note: Call to Earth is a CNN editorial series committed to reporting on the environmental challenges facing our planet, together with the solutions. Rolex’s Perpetual Planet initiative has partnered with CNN to drive awareness and education around key sustainability issues and to inspire positive action.
A new form of real estate is popping up along the beaches of South Africa and on the dry, barren islands off its coast – tiny white beach huts. With good ventilation and a sea view, they are just big enough to fit a family of African penguins. Their unique selling point: a safe and cool place for penguins to breed.
African penguins, unlike their relatives that live in snow and ice, thrive in the cold currents of the South Atlantic Ocean. But when they come to land, their thick black coat absorbs the heat, and they desperately look for cover – both for themselves and their fragile eggs.
Historically, the penguins dug burrows in layers of guano – accumulated seabird and bat feces – that lined Africa’s penguin colonies, but in the 19th century, traders started selling guano as fertilizer, leaving the penguins and their eggs increasingly exposed to predators and the scorching sun.
This, combined with other threats such as egg poaching, overfishing and climate change, has caused African penguin populations to plummet. In 2019, there were thought to be less than 20,000 breeding pairs, down from an estimated 1.5 to 3 million birds in 1900. For more than a decade, the species has been listed as endangered by the IUCN.
That’s why conservationists have come to the rescue with the African Penguin Nest Project – a coordinated effort between Dallas Zoo, AZA Safe, the Pan-African Association of Zoos and Aquaria, and the Dyer Island Conservation Trust – which aims to deploy artificial nests to give penguin parents a safe and shaded place to raise their chicks.
Imitating Mother Nature
While guano trade petered out by the late 1800s, replicating the layers that accumulated over thousands of years isn’t an option. Seabird populations have declined so much over time, there are simply not enough birds to recreate it, says Kevin Graham, associate curator of birds and ectotherms at Dallas Zoo and coordinator of the African Penguin Nest Project. Some estimate it would take around 600 years to produce one usable guano layer, he adds.
Instead, the project decided to build artificial nests. At first glance, they look fairly simple – a domed structure made from two molded shells of fabric coated in ceramic slurry, with a small entrance measuring about 20 centimeters wide. But the design took years to develop, as Graham and other scientists closely studied old guano nests and worked out how best to “emulate Mother Nature.”
Getting the right temperature and humidity inside the nest was the hardest and most important part, says Graham. The two-layer design and ventilation holes create an air conditioning effect, while the white paint reflects the sun, helping to maintain an interior temperature of less than 35 degrees Celsius. “Eggs are an extremely delicate structure; they’re only set to be incubated at about 38 to 39 degrees. Any higher than that, there’s a very real risk of the (unborn chicks in the) eggs dying,” he explains.
The project started to deploy the nests in late 2018. “Within a matter of minutes, penguins were running into them,” says Graham. “That tells you how desperate they are for any opportunity to find a safe place to nest.”
Demand for the ceramic homes has been borne out in the data too – they have usage rates of at least 99%, according to Graham, and the rates for successful hatching and fledging chicks in artificial nests are much higher than those in natural ones elsewhere.
More than 500 nests have been installed on Dyer Island, a bare and windswept isle off the coast of South Africa’s Western Cape that was once home to some of the biggest colonies of African penguins.
CapeNature, the governmental organization looking after the area, says it has already started to see the benefits.
“With the historic removal of guano, (the nests) are the next-best option to giving penguins that opportunity and ensuring the survival of those chicks and the fledglings,” says Andrae Marais, CapeNature’s conservation manager for the island. He adds that while it’s a step in the right direction, it must be combined with other conservation efforts, such as implementing no fishing zones around the colonies to ensure food security for the birds.
Graham agrees that population recovery depends on more than just giving African penguins a safe place to breed. It’s not simply a case of “we give them a nest, the species is saved,” he says. “It’s a big part of it, but there has to be more.”
Flying the nest
The project relies on donations, with individuals or groups able to sponsor individual nests. Each one costs around $75 to build and is expected to last 15 years or more, so Graham expects a single nest to accommodate around 30 nesting events, and potentially up to 60 chicks.
Related: Desert elephants are finding friends in the drylands of Namibia
To date, the African Penguin Nest Project has installed more than 1,500 nests across five of South Africa’s penguin colonies, and plans to expand into Namibia next year, the only other country with breeding populations of the species.
“This is still just a drop in the bucket,” says Graham, who anticipates they will need to deploy at least 4,500 more ceramic homes to protect penguins currently nesting in exposed areas. “The goal is that every penguin that needs a nest will get one.”
