Two male African penguins which have formed a same sex partnership with one another at Toronto Zoo are to be separated and encouraged to mate with females.
With Pedro and Buddy’s species on the brink of extinction, Tom Mason, curator of birds and invertebrates, insists that the zoo cannot afford to let a season go by without the pair passing on their genes.
“If [Pedro and Buddy] weren’t genetically important, then we’d let them do their thing,” Mr Mason explained.
The plight of Buddy, 20, and Pedro, 10, has caused something of an outcry in Canada. The birds, both bred in captivity, arrived in Toronto this spring from Pittsburgh’s National Aviary to form part of a display of 12 African penguins — six male, six female — that opened at the zoo in May.
Keepers noticed that during the day all 12 penguins swam and frolicked together in their enclosure, which includes a pool with underwater viewing windows. They hoped that Buddy and Pedro would “pair-bond” with a couple of eligible females.
In fact the male birds had already formed a connection with one another as members of a bachelor flock, and the relationship continued after they arrived in Canada.
“They do courtship and mating behaviours that females and males would do,’’ said one keeper.
This behaviour includes making a “braying’’ sound as a mating call. They defend their territory, preen each other, and are constantly standing alone together.
“It’s a complicated issue, but they seem to be in a loving relationship of some sort,’’ says Joe Torzsok, chair of the Toronto zoo board.
The gay partnership has caused talk. “This is all new for us,’’ said another keeper, pointing out that the zoo hasn’t had African penguins on display since 1993.
There has been an outcry since it emerged that keepers have decided to step in and separate Pedro and Buddy. The zoo justifies the move because the animals are part of an endangered species.
Once there were millions of African penguins living on the coast of South Africa. In the 1990s, an estimated 225,000 still lived in the wild. Nowadays the number is closer to 60,000 — and dropping at a rate of two per cent a year.
The cause, biologists suspect, is a combination of pollution, competition from commercial fisheries, and changing ocean currents that are driving food sources further and further away from penguin breeding grounds on the coast. The International Union for Conservation of Nature warns that wild stocks of African penguins could be completely wiped out before the end of the century.
“We have to keep an eye on the population all the time, because if we let things slide we could lose the population forever,” Mr. Mason said.
The sexual partners of almost all captive African penguins are mapped by researchers at Chicago’s Population Management Center. Scientists arrange for penguins to be paired, split up and even moved to different zoos in order to maximise genetic diversity.
Penguins are particularly difficult to breed in captivity. If Pedro and Buddy were another kind of animal, zookeepers could simply extract their sperm and use it to artificially inseminate a female. But among penguins, the labour-intensive process of incubating and hatching an egg is next to impossible for one parent.
There is one of ray of light on the horizon for Pedro and Buddy – their separation is likely to be temporary. Once they have succeeded in inseminating their respective female partners, keepers expect them to incubate their eggs side by side.
Once breeding season is up, Pedro and Buddy will “probably” ditch their female partners and reunite, said Bill Rapley, executive director for conservation, education and wildlife at the Toronto Zoo.
In 2004, Roy and Silo, a pair of male chinstrap penguins at New York’s Central Park Zoo became famous for incubating and rearing an egg given to them by zookeepers. The pair’s story was later retold in a bestselling children’s book, “And Tango Makes Three.”
Roy and Silo eventually split when Silo became interested in a female penguin.
A 2010 study of penguin homosexuality by France’s Centre for Functional and Evolutionary Ecology concluded that penguin homosexuality is widespread, but rarely lasts longer than a few years.