Birds Using Anti-Bird Spikes to Build Nests

Birds all over Europe are using hard metal spikes–originally intended to deter bird perching–in their nests. However, this is not the first documentation of birds using harsh man-made materials for nesting; the first report of a crow’s nest made of barbed wire dates back to 1933, and more modern reports document birds’ use of nails, screws, and syringes for their nests. These metal-spiked nests are mainly built by magpies and crows in Scotland, Holland and Belgium.

The metal spikes provide many benefits to the birds’ nests, such as structural support, protection against predators, and even as a signal of high mate-quality. According to researcher Auke-Florian Hiemstra from the Naturalis Biodiversity Center and Leiden University in the Netherlands, who first came across such a nest in a hospital courtyard in Belgium after it was spotted by a patient, the metal spikes appear to have a similar function to more natural materials, such as thorns. However, there can also be dangers to using man-made materials in nests. For example, metal spikes may get cold at night and harm chicks or the spikes can collect materials that can be harmful to the birds.