Parenting a flock of northern bald ibis is demanding work. For the past six months, biologists Barbara Steininger and Helena Wehner have spent every day feeding and growing them by hand. endangered chicks. At that time they could not pass on the duties of reception to anyone else; young birds needed it. footprint upon them and them alone.
Steininger and Wehner then took to the skies to guide their young charges on the birds’ first migration. They boarded an ultralight aircraft in mid-August in Rosegg (Austria).to begin a journey of approximately 2,800 kilometers, which ended on October 3 in a winter area in Andalusia, Spain. There the two foster parents said their last goodbyes to the birds they helped raise.
“Finally, you have to release them in the wintering grounds and accept that they are now independent and don’t need you anymore,” says Johannes Fritz, who leads the team that reintroduces northern bald eagles into the wild in Europe. Since 2004 he has been piloting ultralight aircraft on these guided migrations.
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Northern bald ibis migrating.
Waldrappteam Conservation and Research
Bald ibis migration
Every autumn, when the days are shorter and the weather cooler, the migratory instinct of the ibis kicks in, prompting them to seek a warmer climate to spend the winter. Usually the parents would lead their young on the first migration to show them the route. But birds’ knowledge of flight paths has largely been lost. That’s because the species has been hunted to near extinction in its native habitat of North Africa, Central Europe and the Middle East. In Europe the species ran into trouble in 1504, when the archbishop of Salzburg made it illegal to shoot the birds. Despite this ban and some early conservation efforts, the European Bald Ibis was last seen in the wild in 1621, and only a small number have survived, mainly in Morocco.
Today, thanks to careful management and reintroduction efforts, small sedentary (non-migratory) populations exist in the wild in Turkey and Spain. But the inability to migrate can endanger their survival. Migratory birds evolved to breed in one climate and spend the winter in another. Splitting their time between the two habitats could give them better access to food and greater reproductive success, said Ana González-Prieto, a bird ecologist with the Canadian Wildlife Service, who is not involved in the reintroduction effort.
To have the best chance of success in the wild, northern bald ibis populations must migrate, Fritz says. So his group has taken on the responsibility of teaching the young birds the route. They were initially inspired by the 1996 film fly away home in which a girl and her father help a flock of geese migrate using an ultralight aircraft. The film was based on the work of the late Bill Lishman, the sculptor and filmmaker who used an airplane to teach captive-bred birds to migrate. Lishman founded Operation Migration, an organization that deployed scientists dressed as birds to guide endangered birds, such as those that were nearly extinct, on migratory routes across North America.
Fly home with Bald Ibis
This method, called human-led migration, is resource- and time-consuming, but for bald ibis, it seems to be working. The process begins in the spring with foster parents hand-rearing chicks taken from captive-bred populations. Then, at the end of the summer, the conservation team starts its journey. An ultralight aircraft, powered by a propeller and held aloft by a large yellow parachute, takes off, flying hundreds of meters above the ground. It flies at the speed of birds, faster than 50 kilometers per hour. The flying contraption has seats for two people: Fritz, who got his pilot’s license for it, and one of his two foster parents, who take turns in sky duties.
When the plane takes off, the host parents call in German for the birds to follow, shouting:come on, Come on!” through a megaphone over the drone of the engine. Once in the air, the birds will sometimes hover close to the aircraft and greet their host parent by waving their bill up and down and chirping. After being greeted by the host parents, they take their position in the formation.
“It’s very emotional,” says Fritz. “As a pilot I have the privilege of experiencing this in the sky.”
After flying for four or five hours, they will return to the ground. At least another dozen crew members will go ahead and set up camp: a temporary aviary for the birds and tents for the team members. The next day, they do it again.
This year Fritz’s group shepherded 36 birds, the largest group of young Northern Baldbirds ever. But like human teenagers, birds don’t always cooperate. This trip was “a bit stressful because the birds refuse to follow” at times, Fritz says. Sometimes when the plane took off, the birds stayed on the ground. “The foster mother calls the birds (as) we circle in the distance,” says Fritz, “but they stay at the airport.”
These changes in the birds’ “motivational state” are challenging but normal, Fritz says. If the plane turned enough, eventually the birds followed; Being temporarily separated from foster parents is “a kind of social punishment,” he says. “When they follow through, they are rewarded only by contact with the foster parent.”
At the beginning of the month, all 36 birds arrived in Andalusia, although only 10 managed to fly all the way. The remaining 26 were taken for the final leg of the journey. The northern bald ibis are joining a reintroduced flock and will spend their first sweet winter in the wild. When the days begin to lengthen again, hopefully they will migrate on their own to the Alps to breed. Most of the birds are equipped with solar-powered GPS tags so that conservationists can monitor and manage the wild population.
Reaching Permanent Population
In the first years of the program, no birds returned to the Alps from their initial wintering site in Tuscany, Italy. Then, in July 2011, the first bird returned. In the four generations since then, the wild migratory population has grown to 256 birds. They have a relatively high reproductive success rate, having about three chicks per nest, compared to sedentary Andalusian populations, and produce an average of one chick per nest.
Until the population reaches a sustainable level, researchers will need to continue hand-rearing and guiding more chicks on their first migration. A study published in 2023 found that the population close to being self-sustaining—or capable of progressing without human intervention—but it has not yet crossed that threshold. The program currently has partial funding guaranteed through the European Union until 2028.
Northern bald ibis are migrating in formation.
Waldrappteam Conservation and Research
The original human-led migration organization, Operation Migration, from 2001 to 2015 recovered a migratory population of Whooping Cranes from Wisconsin to Florida. The US Fish and Wildlife Service ultimately withdrew support for the project.
The Whooping Crane and Bald Ibis programs are experimental and invasive. And they are very visible to the public. “There was a lot of skepticism in the early years of the project,” says Fritz. “In the meantime I think the scientific community and conservationists recognize the potential of the methods.”
“The main strength of these projects is the positive conservation results, as shown by the growth of wild populations,” says González-Prieto. “They also encourage action to protect even declining wild-breeding populations before they face extinction” because they demonstrate how resource-intensive it can be to bring a species back from local extinction.
Such methods may become increasingly important as climate change continues to alter how birds migrate and where they spend the winter. Fritz’s team originally flew their birds across the Alps to Tuscany, but the reintroduced birds are leaving their summer homes later and later each year because of climate change, waiting until autumn rather than late summer.
“These birds have delayed their migration until early November, when the thermals (air currents) are too weak to travel across the Alps,” says González-Prieto. “As a result, the birds get stuck in unsuitable habitats in the valley.”
Last year Fritz’s team started flying to Spain instead of Italy, a route that does not have to cross the Alps. As these environmental changes continue, humans may need to intervene more and more to keep species migrating. “In times of climate change these changes are too fast for species to cope with,” he says.
“It is clear that the disappearance of the bald ibis is the responsibility of humans”, he added. “I think it’s worth doing everything possible” to save them.
