Birds Use Anti-Bird Spikes to Construct Nests: Crows and Magpies Example

Some avian dwellings are becoming quite metal.

In Belgium and the Netherlands, crows and magpies are constructing their nests using anti-bird spikes. These metal skewers are commonly placed on buildings and trees to deter birds from gathering there.

“As a nest researcher, these are the most extraordinary bird nests I have ever witnessed,” tweeted Auke-Florian Hiemstra, a biologist at the Netherlands’ Naturalis Biodiversity Center and lead author of a recent scientific paper on the subject published in the journal Deinsea.

While it’s not uncommon for birds to include artificial objects in their nests, the recent research marks the “first well-documented study” of crow and magpie nests made predominantly of anti-bird spikes, according to the paper.

Hiemstra referred to the tactic as a “brilliant comeback” on the part of the birds in an interview with The New York Times.

“We’re trying to get rid of birds, and the birds are collecting our metal spikes and actually using them to breed more birds in these nests,” he explained.

The birds are able to construct the nests in a way that avoids injury from the spikes. Additionally, there is evidence suggesting that magpies are utilizing the spikes creatively for predator deterrence. Magpies often incorporate spiky materials like thorns to discourage predators, and the outward-facing positioning of the spikes in the nests implies that they serve a similar purpose.

Kees Moeliker, director of the Natural History Museum Rotterdam, told The Guardian that crows and magpies have been observed actively removing spike strips from buildings.

The audacious behavior of the birds has garnered praise from bird enthusiasts on social media. Crow researcher Kaeli Swift, who explained the study on TikTok, added, “I am absolutely fascinated by this bird rebellion.”