A team of Dutch researchers has discovered that magpies and crows are using metal spikes designed to keep them away from certain urban areas to reinforce their own nests and keep intruders at bay.

Scientists have known for a while that magpies and crows are some of the most intelligent birds in the world, but even they were baffled by their amazing ability to adapt to hostile urban environments. It’s not unusual for birds to use human trash and debris as tools and building materials for their nests, button see them use the very things we humans use against them was nothing short of baffling for researchers at the Natural History Museum in Rotterdam and the Naturalis Biodiversity Center in Leiden, in the Netherlands.

Photo: Auke-Florian Hiemstra / Naturalis Biodiversity Center

“I really thought I’d seen it all,” Kees Moeliker, the director of the Natural History Museum Rotterdam, told The Guardian. “I didn’t expect this. These anti-bird spikes are meant to deter birds, they are supposed to scare them off, but on the contrary, the birds just utilize them.”

Nests recovered by researchers from trees in Rotterdam in the Netherlands and Antwerp in Belgium were made almost exclusively out of strips of sharp metallic anti-bird spikes designed to keep birds away. These discoveries prompted a scientific investigation that discovered similar bird architecture in various other locations in the Netherlands and one as far as Glasgow, Scotland.

One particularly impressive magpie nest was discovered in the courtyard of a hospital in Antwerp, Belgium. It was made up of around 1,500 anti-bird spikes, most of which seemed to be positioned with the sharp point outwards, as protection against intruders. After discovering it, researchers checked the roof od the hospital and confirmed that around 50 meters of anti-bird spike strips had been ripped off the building, leaving only the glue used to fix them in place.

Photo: Jaime Dantas/Unsplash

“For the first few minutes, I just stared at it – this strange, beautiful, weird nest,” biologist Auke-Florian Hiemstra told the BBC. “Even for me as a nest researcher, these are the craziest bird nests I’ve ever seen. They are incredible fortresses – like a bunker for birds.”

Birds have been known to incorporate sharp objects, from pointy branches to nails, screws, and barbed wire into their nests as protection, but the use of anti-bird spikes is kind of ironic, as they are the very things used to keep them away. To scientists like Hiemstra, this is a sort of “beautiful revenge”.

“They are using the material that we made to keep them away, to make a nest to make more birds,” the biologist said.

 

“I was really struck by the irony, to take anti-bird devices and use them to their own ends,” Dr Jim Reynolds, an ornithologist at the University of Birmingham, agreed. They are even more amazing than I thought they were.”

A few years back, we wrote about rich people in the UK installing anti-bird spikes on trees to stop birds from pooping on their luxury cars, but I guess the birds had the last laugh…