War reshapes nature: Birds build nests from fiber-optic drone cables

Bird nests woven from fiber-optic cables — the same cables used to guide drones and shield them from jamming along the Ukraine-Russia front line — have been discovered, drawing wide attention. Researchers plan to trace which species built them and how.

The nests, made from fiber-optic cable and grass, are on display at the National Museum of the History of Ukraine in the Second World War in Kyiv, according to Reuters, CNN and other international outlets Wednesday.

Reuters said the nests offer a window into how more than four years of war have transformed the natural environment.

Since the war began in 2022, drones have emerged as a weapon capable of reshaping the strategic and tactical thinking of both sides. Ukraine has poured heavy investment into drones to counter Russia's large-scale deployment of conventional equipment — tanks, armored vehicles and artillery — and to offset its disadvantages in hardware and manpower.

As drones have taken on a central role in both offense and defense, countermeasures against them have grown increasingly sophisticated.

The fiber-optic cables the birds used for their nests serve to guide attack drones toward targets and protect them from electronic jamming.

The cables are strung like a spider's web across more than 1,200 kilometers of front line, tangled among roadside trees and draped over village rooftops.

The discovery came to light after Ukrainian soldiers shared photographs online.

Mykhailo Mletchko, a member of the Ukrainian military, told CNN he was stunned to see birds nesting with fiber-optic cable. "It's amazing, it's impressive," he said.

It remains unclear which species built the nests or how the birds gathered the cable.

Researchers plan to extract DNA from the nests to identify what built them, and will also analyze the extent of fiber-optic material woven into the structures.

One of the nests is on display at the Kyiv war museum, while a second is being studied in the Netherlands before being returned to Ukraine.

Dutch biologist Auke-Florian Hiemstra told Reuters he had seen many nests in his career but nothing like these. "We'll look for DNA traces left in the nest to find out who made it," he said.

Anya Hrynko, a senior researcher at the Kyiv war museum, said the birds had begun repurposing discarded cables to build their nests. "Things like these nests made of fiber-optic fragments show how the war is changing nature," she said.