Birds are very ingenious creatures and some, especially corvids, are incredibly smart. They have been known to rip anti-bird spikes off rooves but it still came as a surprise when scientists discovered they were making nests out of them.
It began when a patient at an Antwerp hospital spotted a large and unusual magpie nest, high up in a tree in the facility’s courtyard. Upon closer examination, that nest was found to contain approximately 1,500 anti-bird spikes. They had been pulled by the birds, from about 50 metres of the hospital’s eaves.
The magpies placed the spikes so they protruded outward from the roofed nest, in order to discourage other birds from going in and eating the eggs or chicks. Magpies and other related birds regularly use other sharp building materials, such as barbed wire and thorny branches, for the same purpose as magpie nests are predated by crows.
What else can you use to make a nest?
Nesting can be a tricky business and finding materials even more so. You might as well use what you can find if you’re a bird.
Coots in the canals of Leiden make their nest of plastic pollution, for example. And for a long time people used to offer yarn scraps, human hair, dryer lint and pet fur for birds to use – all bad news, though so please don’t.
Apparently you can offer yard clippings and pine needles with no problem. Experts also say that cotton batting, instead of yarn, is OK to offer as well, since the material is natural and breaks apart easily. Short natural fibres like coconut and untreated/undyed lichen and moss are examples of good nesting material.
Image credit: Auke-Florian Hiemstra/Hiemstra et al., Deinsea, 2023 (CC BY 4.0)