“Even for me as a nest researcher, these are the craziest bird nests I’ve ever seen.”

Hostile architecture is a design strategy that restricts access to public space. Spikes protruding from doorways, fences under stairs, and curved benches that require the user to stabilize themselves with their feet are examples of the inhumane practice that deters unhoused, poor, and young people from gathering in urban areas. The approach also applies to non-human species, and birds are primary targets—a few years back, a Bristol tree was even spotted with spines lining its branches.

But as researchers from Naturalis Biodiversity Center and the Natural History Museum Rotterdam have discovered, our feathered friends have more ingenuity than architects thought. A paper published this month in Deinsea highlights several examples of magpies and carrion crows building nests with strips of anti-bird spikes in both Rotterdam and Antwerp. Magpies are particularly enterprising and use pointed edges for their original purpose: many have lined the roofs of their homes with the spikes to deter predators from snatching eggs.

Read More at Colossal

Read the rest at Colossal