Why eagles have largely gone extinct from Western Europe

Transcript

A MARTÍNEZ, HOST:

The war in Ukraine is not only destroying the lives of many humans - it's also disrupting the lives of animals.

MICHEL MARTIN, HOST:

One of them is the greater spotted eagle.

ADHAM ASHTON-BUTT: It's this amazing, huge, charismatic eagle that specializes in pretty remote wetland environments. They've largely gone extinct from Western Europe.

MARTIN: That's Adham Ashton-Butt. He is a senior research biologist for the British Trust for Ornithology. He says there are less than 10,000 greater spotted eagles left in the world.

MARTÍNEZ: Many live in the wetlands and forests of Belarus and Ukraine.

ASHTON-BUTT: Southern Belarus is one of their strongholds, where there's over 300 breeding pairs.

MARTÍNEZ: But the war in Ukraine has complicated the eagles' migration to their breeding ground in Belarus. The male greater spotted eagles usually travel there in the winter from East Africa, and the females from southern Europe. To get to Belarus, they go through Ukraine.

ASHTON-BUTT: Usually, they go quite directly, and stop over at these wetland sites to kind of refuel on the way.

MARTIN: But since Russia's full-on invasion of Ukraine in 2022, researchers started to see something different.

ASHTON-BUTT: They were taking a lot longer to migrate. They were going less directly, so they were kind of moving in a less of a straight line, and they also weren't stopping over at their usual refueling sites.

MARTIN: He says the loud noises from shelling, explosions or troop movements were causing the birds to change their migration path, to zigzag erratically.

ASHTON-BUTT: I think something akin to panic is probably what's going on.

MARTÍNEZ: Russia drops thousands of bombs and launches hundreds of drones toward Ukrainian targets each month. The eagles eventually get to their destination, but only after flying up to 60 additional miles.

ASHTON-BUTT: The increase in flight and the later arrival at their breeding grounds might mean that they're less fit and they've got less energy to breed successfully.

MARTIN: This is especially important for a bird like the greater spotted eagle, which is considered a vulnerable species, Ashton-Butt says.

ASHTON-BUTT: They only have one chick per year and their breeding success is around 50%, so if they miss out on breeding for a year, then it can really impact the population, which is relatively small.

MARTÍNEZ: These findings are detailed in a study co-authored by Ashton-Butt and published this month by the journal Current Biology, but how conflict impacts animals is not widely known, mostly because of how dangerous gathering data in the field can be.

MARTIN: Ashton-Butt says what is happening to the greater spotted eagle is evidence of the impact people have on nature, and why migratory bird populations are declining around the globe.

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