One of the world’s rarest birds, once thought to be extinct, successfully bred in the wild late last year. The crop of ducklings marks a victory for conservation groups that have been working for more than a decade to save the species.
In November, conservationists celebrated the appearance of 12 Madagascar Pochard (Aythya innotata) ducklings on Lake Sofia in northern Madagascar. They had introduced a set of young adult pochards there in December 2018 but did not expect them to reproduce so quickly. Diving ducks normally don’t breed until they are 2 years old.
“We were very surprised and excited to have chicks just one year after introducing the ducks,” said Felix Razafindrajao, a wetlands manager for Durrell Wildlife Conservation Trust, a group based on Jersey in the British Isles. In addition to the 12 ducklings, which came in two broods, there are also eight pochard eggs in the marshes that should hatch in the next few weeks, he said.
The pochard was once common in Madagascar’s highlands, but the population declined rapidly in the mid-20th century. Besides one male found in 1991, there were no confirmed sightings between 1970 and 2006, when a scientist from U.S conservation group The Peregrine Fund happened to spot a few of the ducks in a volcanic lake in northern Madagascar.
Decades-long efforts to find the duck through surveys and public campaigns had, it turned out, been too geographically restricted. The search had focused on the center of the high plateau, and especially the Lake Alaotra region, where the pochard, known locally as fotsimaso (“white eyes”), was once common. But the duck was in the far fringes of the high plateau.
“Everybody was looking for the duck in the high plateau, but they forgot about the high plateau in the northwest,” said Richard Lewis, Durrell’s country director.
The rediscovered pochards were in fact living in a mile-high lake, surrounded by what Lewis called a “fabulous bit of forest up in the middle of nowhere,” where there was little deforestation or rice cultivation. The Bemanevika site, some 32 to 40 kilometers (20 to 25 miles) northwest of the town of Bealanana, is now a protected area, having received that status partly because of the pochard’s presence. The site includes four shallow lakes, but the pochards usually stay on the one where they were found and breed in its papyrus marshes.
After 2006, scientists determined that Bemanevika was not an ideal place for the pochard population to grow because of the topography of the lake the pochards kept to and the extremely high death rate of ducklings. “This appears to be an example of a Critically Endangered species whose last refuge is in habitat that is not ideal, but is undisturbed,” wrote the authors of a 2015 study in Bird Conservation International.
In 2009, Durrell and partner organizations removed pochard eggs from the wild and started a captive-breeding program in the regional capital of Antsohihy. Finally, in December 2018, they reintroduced 21 pochards into the wild at Lake Sofia, about 50 km (30 miles) southeast of the Bemanevika site where the bird was rediscovered.
A precarious existence
Despite the recent success, the pochard’s existence as a species remains precarious, with its total population measurable in the dozens. More than a year after reintroduction, just nine of the 21 adult pochards live at Lake Sofia; one died, and the remainder are unaccounted for. (The ducks have identification rings but no radio or satellite tracking tags.) At Bemanevika, meanwhile, there are just over 50 pochards. Durrell and its partners currently have 94 pochards in captivity at two facilities in Antsohihy.
The story behind the Madagascar pochard’s sad decline is unclear. Conservationists believe the ducks nearly went extinct because of a lack of food. The pochards typically spend one to two minutes underwater at a stretch, diving for food at the bottom of lakes. Though little research was done on the pochard before its disappearance, the 2015 study indicated that the ducks eat benthic, or underwater, insects such as the aquatic larvae of caddis flies. It seems that such insect populations plummeted, likely due to oxygen depletion in lake water caused by deforestation or agricultural pesticide runoff. And as the bugs declined, so too did the fortunes of the diving duck.
The destruction of Madagascar’s wetlands made it difficult to find a place to reintroduce the pochards. Durrell did “cheap and cheerful benthic sampling” at wetlands across the high plateau, but the amount of worms and insects was far too low to support pochard survival, Lewis said. Even at Lake Sofia, the chosen site, food is not plentiful on the lake bottom, so conservationists supplement the pochard diet with duck food flown in from the United Kingdom. (Lewis said they intend to shift to local sources once they can identify some that is free from a mold lethal to ducks.)
The conservationists say their efforts to save the pochard dovetail with their community work — that is, what’s good for the pochard is good for human beings. “The pochard depends on a healthy wetland, and that will be more productive for human use as well,” Lewis said.
Bamford, A. J., Sam, T. S., Razafindrajao, F., Robson, H., Woolaver, L. G., & René de Roland, L. A. (2015). The status and ecology of the last wild population of Madagascar Pochard Aythya innotata. Bird Conservation International, 25(1), 97-110. doi:10.1017/s0959270914000033