In an attempt to boost the population of endangered Galápagos penguins, researchers have been building new nests for them on the islands.
Biologists hope that the nests will help increase the population of the endangered Galápagos penguins, which have experienced a population decline of more than 50 percent since the 1970s, and face a 30 percent chance of extinction in this century, according to the New England Aquarium.
Galápagos penguins are the only penguin species whose range includes part of the Northern Hemisphere as the islands are located along the equator. Because of continuous warm temperatures at the equator, Galápagos penguins need shaded nests to breed.
The birds use crevices in the rocks, lava tubes or similar spaces to find relief from the heat and protection from predators.
"One of the biggest problems is the introduced species of predators," including pigs, dogs, cats and rats, said researcher Dee Boersma of the University of Washington. "We went to lengths to build nests in places where there aren't introduced predators."
Their habitat also has declined, she said, and new nests are needed if the population is to stabilize.
This September, Boersma and her team built 120 of these crevices for the penguins. They created holes just large enough to serve as nests along the volcanic shoreline of three islands in the Galápagos and several smaller islets.
"Our whole goal is to increase the population of Galápagos penguins, and the way to do that is to make sure that when conditions are good, when they're not food-challenged, that all of them will be able to breed," Boersma said.
The penguin species is one of two listed as endangered by the U.S. Fish and Wildlife Service, and according to Boersma, new nests are needed if the population is to stabilize.
Using local lava, Boersma and her team built 100 shaded nests in clusters that are relatively close together, and 20 nests that are farther away.
Most of the islands of the Galápagos, which are part of Ecuador, and surrounding waters are protected as a biological marine reserve and national park, and are a United Nations World Heritage site. Until recently, the islands were also included on World Heritage’s “Sites in Danger” list.
La Niña boost
Climate cycles can play havoc with Galápagos penguin reproduction. The penguins depend on cold ocean currents that rise to the surface and bring plentiful food. During El Niño years, those currents fail and most marine species have trouble finding food. During La Niña cycles, those rising cold currents increase and bring a plentiful supply of nutrients to support small fish on which the penguins feed.
Boersma hopes the new nesting sites were in place soon enough to have a positive effect as La Niña conditions take hold in the Galápagos and bring plentiful food to the penguins.
"We found everything from eggs to small chicks to near-fledglings because the food is so good because of La Niña," she said. "The penguins are ready, if the food stays, to begin breeding. The question is will they find these new nest sites in time."
She expects to return to the Galápagos in February to evaluate the project's progress.