Some bird nests are getting pretty metal.
Crows and magpies in Belgium and the Netherlands have constructed their nests using anti-bird spikes ― metal skewers that people place on buildings and sometimes even on trees to prevent birds from gathering there.
“Even for me as a nest researcher, these are the craziest bird nests I’ve ever seen,” tweeted Auke-Florian Hiemstra, a biologist at the Netherlands’ Naturalis Biodiversity Center and lead author of a scientific paper on the phenomenon published in the journal Deinsea this week.
Birds incorporating sharp, human-made objects into their nests isn’t new, but the latest research is the “first well-documented study” on crow and magpie nests that “almost entirely consist of material that is meant to deter birds: anti-bird spikes,” the paper states.
Speaking to The New York Times, Hiemstra called the tactic “a brilliant comeback” on the part of the birds.
“We’re trying to get rid of birds, the birds are collecting our metal spikes and actually making more birds in these nests,” he said.
The animals can construct the nests so the spikes don’t hurt them. And there’s evidence that magpies might be utilizing the spikes in a particularly ingenious way. Those birds are known to build nests that include spiky materials like thorns to deter predators. And in the nests researchers examined, the bird spikes were positioned in an outward-facing way, suggesting that they also serve a predator-prevention purpose.
Crows and magpies have also been observed actively ripping the spike strips off buildings, Kees Moeliker, director of the Natural History Museum Rotterdam, told The Guardian.
Bird enthusiasts have celebrated the seemingly defiant behavior on social media. That includes avian ecologist and crow researcher Kaeli Swift, who explained the study to her followers on TikTok and added, “I am absolutely living for the bird rebellion.”
