Two male Humboldt penguins at Rosamond Gifford Zoo in New York are doing a "great job" of raising their foster hatchling, the zoo's director has said.
While a number of zoos around the world have seen same-sex penguins incubate eggs and raise the resulting chicks together, penguins Elmer and Lima are a first for the Syracuse-based Rosamond Gifford Zoo.
In a statement, the zoo said it had previously seen at least two breeding pairs of penguins unintentionally break their fertilized eggs. So, in order to better the chances of successfully hatching a baby penguin, zookeepers tend to give an egg to a more successful pair of penguins.
Ted Fox, the zoo's director, said that incubating eggs takes practice and that not all penguin pairs are naturally good at it.
"Some pairs, when given a dummy egg, will sit on the nest but leave the egg to the side and not incubate it correctly, or they’ll fight for who is going to sit on it when," he said.
"That’s how we evaluate who will be good foster parents - and Elmer and Lima were exemplary in every aspect of egg care."
On December 23, the zoo found that an egg laid by female penguin Poquita and her partner Vente contained a viable embryo. So, they proceeded to swap it with Elmer and Lima's dummy egg and allow the pair to incubate it instead.
The same-sex penguins took turns incubating the egg until it hatched, and, now, the pair are warming and feeding the chick.
"At our first health check when the chick was five days old, it weighed 226 grams (8 ounces)," Fox said. "It continues to be brooded and cared for by both Elmer and Lima, who are doing a great job. And once they have experience doing this and continue to do it well, they will be considered to foster future eggs."
This certainly isn't the first time that a same-sex penguin couple has fostered chicks.
Previous same-sex foster parents include Electra and Viola, two female Gentoo penguins at the Oceanogràfic Valencia aquarium in Spain; Skipper and Ping, two male king penguins at Berlin Zoo, and Eduardo and Rio, two male Magellanic penguins at San Francisco Zoo.
