Rebel birds build nests from anti-bird pins

Biologists have come up with the latest innovation in nest building: bird nests are made of nest-resistant spines. Researchers from the Center for Biodiversity Naturalists and the Natural History Museum Rotterdam collected these particular nests for the first time and described this extraordinary behavior in a scientific publication as ‘a final adaptation for life in the city.’

If you look around the cities, you can see anti-bird spikes on many buildings. Sharp metal spikes were placed to scare away birds, and to prevent them from building nests. But birds are not so easy to scare, now they appear. Researchers from two Dutch natural history museums collected the nests of Eurasian carrion crows and magpies built mostly with materials that should deter birds: bird nests made of anti-bird spikes. “It’s like a joke, really” says biologist Auke-Florian Hiemstra of Naturalis: “Even for me as a nest researcher, this is the craziest bird’s nest I’ve ever seen.”

The adaptability and creativity of urban birds seem to know no bounds. Researchers from the Naturalis Biodiversity Center and the Natural History Museum Rotterdam describe this spiky structure in a scientific journal Deinsea. “Just when you think you’ve seen it all after half a century of studying natural history, these inventive crows and magpies really blow me away again,” said Kees Moeliker, director of the Rotterdam Museum of Natural History and co-author of the scholarly publication. .

1500 metal nails
It started with the discovery of a large nest in Antwerp, in the hospital grounds, which one of the patients found. High in the trees, magpies build large nests of up to 1,500 metal spikes. For this particular nest, birds have pulled anti-bird pins 50 meters (150 feet) from the roof. “An impenetrable fortress,” says Hiemstra, “because magpies seem to use pins in exactly the same way we do: to keep other birds away from their nests.”

Crows make roofs over their nests to prevent robbery of their eggs and chicks, and they specifically seek out thorns in nature for this purpose. Spiky branches keep hungry egg raiders away. In town there is another option: anti-bird spikes. “They really were made to keep birds away,” says Hiemstra, “looks like they are used by birds too.”

Rebellious bird
And it’s not just a pair of magpies who have ventured into bird repellant. The article describes several magpie nests with anti-bird spines as the nesting material. This behavior has been seen in the Netherlands, Belgium and Scotland. Other sharp materials, such as barbed wire and knitting needles, are also used by magpies for the roof of their nests. Crow’s nests made of anti-bird spikes are currently only known from the Netherlands.

It is well known that birds are not easily deterred by safety pins. The ‘Parkdale Pigeon’ gained notoriety for not being frightened off by the anti-bird pegs and several videos show the rebellious behavior of the bird ripping spikes from the roof. A collaboration between the Leiden and Rotterdam museums has now resulted in the first scientific publication demonstrating that birds also use the anti-bird pins as nesting material.

Condoms and cocaine
Auke-Florian Hiemstra (1992) is doing a PhD in Naturalist and the University of Leiden on the use of artificial materials in animal structures, and has previously published on the use of face masks and plastic plants in bird nests. He also regularly finds condoms, fireworks, cocaine packets, sunglasses and windshield wipers as nesting material for his coot. “Even if sharp bird-repellent spikes are used as nesting material, it seems that anything can end up in a bird’s nest these days. It doesn’t get any crazier than this, right?”

The great anti-magpie pin nest from Antwerp can be seen starting July 11 as a new highlight in the LiveScience Naturalis space, which is free to visit. The Rotterdam Museum of Natural History is displaying a crow’s nest of anti-bird pins in its recently opened ‘National Park Rotterdam’ exhibition, along with a number of other extraordinary constructions of urban animals.

Further information, not for publication

• For questions about publications, contact Auke-Florian Hiemstra.
• Article by Hiemstra et al published in Deinsea.
• For general inquiries, please contact the Naturalis press office via 071 – 7519 648 or (email protected)
• A high resolution version of the image above can be found in this press folder. Credit for press photo: Alexander Schippers. Drone image credit: Mike Muizebelt. Credit nest image: in filename.