No trees, no food, shot for fun … yet Serbia’s imperial eagles are making an improbable return | Birds

AAt the start of each spring, before the trees of northern Serbia begin to leaf out, birdwatchers cross the plains of Vojvodina. They check old nesting sites of eastern imperial eagles, scan solitary trees along field margins and look for signs of new nests.

For years, the work of the Serbian Bird Protection and Study Society (BPSSS) has become more demanding – and more rewarding. In 2017, Serbia had only one breeding pair left. Last year, BPSSS recorded 19 breeding pairs, of which 10 successfully raised young.

Crossing Vojvodina, vast fields stretch to the horizon, crisscrossed by straight farm roads. As agriculture intensified, oaks and poplars were cut down to straighten fields and maximize yields. This has made Vojvodina one of the least forested regions in Europe. In some municipalities, tree cover drops below 1%. “You can drive here for an hour and a half without seeing a single tree taller than five meters,” says Milan Ružić, executive director of BPSSS. “Even if an eagle wants to return, the question is: to which tree?

A lack of trees is one reason the once-widespread imperial eagle has struggled for decades, but it’s not the only one. Its decline began with persecution. “The region has a history of unrest and wars,” explains Ružić. “Every household had a gun. People shot birds of prey for fun or to protect livestock. Raptors were the enemy.”

After World War II, the Yugoslav state carried out extensive poisoning campaigns targeting large carnivores such as wolves and bears, distributing toxic bait to farmers and shepherds. The birds of prey have paid the price. “If you poison a sheep carcass in the open, eagles and vultures will be the first to find it,” says Ružić. “If an eagle is shot, the others find out. With poison, there is no warning.”

With agricultural intensification, species (Aquila heliacus) also lost their food. In Vojvodina, they feed primarily on ground squirrels, or sousliks, which thrive in short-grass pastures. When the cattle moved into the stables and the pastures disappeared, the sousliks also disappeared. “The eagles suddenly lost their nesting trees, their food and their safety,” Ružić explains.

By the late 1980s, only two small populations of imperial eagles remained in Serbia: one in the sands of Deliblato, a steppe east of Belgrade, and another in the hills of Fruška Gora, near Novi Sad. The Deliblato eagles disappeared in the 1990s. Fruška Gora kept its birds until 2015.

Ružić has a theory – unproven, he points out – about what finished them off. After Russia’s annexation of Crimea in 2014, EU sanctions halted fruit exports to Russia. Serbia has filled part of the void. “Fruit production exploded in Fruška Gora. Pastures were transformed into orchards and hundreds of new power lines appeared,” explains Ružić. “For a fragile eagle population, such a change can be fatal.”

While Serbia was losing its birds, a different story was unfolding across the border. Hungary has protected imperial eagles for decades. From 20 pairs in the 1980s, the population now stands at 550 individuals. As Hungarian territories became saturated, young eagles began to disperse south, first arriving in Serbia in 2011. “Hungary became a source population for the region,” says Ružić. Around the time the species disappeared from Fruška Gora, a new pair appeared in northern Serbia.

Encouraged by the EU-funded PannonEagle Life project, the BPSSS decided that Serbia’s last breeding pair would not be allowed to fail. Volunteers guarded the nest throughout the breeding season, camping at a safe distance to avoid any disturbance from farmers, shepherds or curious onlookers. When a storm damaged the nest shortly before fledging, conservationists temporarily removed the chicks to rebuild the structure. The parents returned, the young people survived.

Today, the BPSSS monitors territories, rehabilitates injured eagles and works with communities. “In village cafes we reported that there were fewer imperial eagles throughout the country than people drinking beer in the hall,” says Ružić. “People suddenly cared.”

As it is widely believed that the Imperial Eagle is depicted on Serbia’s national coat of arms, this message carried additional weight. “When you tell people there is an eagle nesting nearby, it becomes a brand: ‘our village has THE eagle’. Immediately, people are less likely to shoot or poison themselves.

The results are visible. Every year the search for nests becomes more and more extensive. New territories are emerging, with the population expanding southward along river corridors at an estimated rate of 15 to 20 km per year.

But the recovery remains fragile. Trees are still rare and imperial eagles are slow to adapt to artificial nesting platforms. “They don’t trust them,” says Ružić. “White-tailed eagles will nest on anything – you could put a refrigerator in a tree and they would use it. Imperial eagles are different. They need time.”

Although Serbia is part of the BalkanDetox Life project, an EU initiative aimed at eradicating wildlife poisoning, the practice persists. Despite bans and awareness campaigns, poisons and toxic pesticides are still widely available and the habit is deeply rooted in the Balkans. “It’s a mentality problem,” says Ružić. “It often starts with a neighbor’s dog barking or a fox taking chickens. Poisoning a piece of meat is an easy and inexpensive solution.” Since 2000, the BPSSS has recorded around 300 poisoning incidents.

Power lines and wind farms pose another danger. Environmental advocates find themselves increasingly at odds with investors, businesses and farmers. Ružić was told he should be “hanged from a pylon”. Serbia’s pro-Russian stance further complicates the research. Importing satellite tags now requires significant paperwork. “We had to sign documents proving that we are using them to track birds, not to fight a bloody war.”

For now, the eagles are holding on. Many birds in Serbia are still young and it can take five years before a newly established pair begins breeding. “They are still learning,” says Ružić. But if a couple survives long enough, their productivity increases with age. Time is on their side.

“The trend has reversed,” says Ružić. “Unless something drastic happens, they’ll keep coming back.”

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