Some birds have been spotted using anti-bird spikes to construct their nests, turning the tables on their intended purpose. A recent study led by biologist Auke-Florian Hiemstra and his team at the Naturalis Biodiversity Center in Leiden, Netherlands, has shed light on this fascinating behavior, highlighting how Eurasian magpies (Pica pica) repurpose the sharp bird-deterrent strips to ward off other birds and safeguard their nests.
The study originated when a patient in Antwerp, Belgium, captured an image of a magpie nest adorned with over 1,500 long, sharp antibird spikes. Intrigued by this peculiar sight, the photo was sent to Hiemstra, who subsequently embarked on a quest to investigate further. The team collected the nest and discovered four more similar nests across cities in the Netherlands and Scotland.
While carrion crows (Corvus corone) incorporated the spikes into the structural framework of their nests, Hiemstra believes that magpies used the spikes as a defensive measure against other birds. Magpies, known for their relatively small size, typically construct domed roofs over their nests to protect their eggs and hatchlings from avian predators. In urban environments where spiny vegetation is scarce, magpies have adapted by using available materials such as nails, screws, and now, antibird spikes.
The incorporation of anti-bird spikes into magpie nests is seen as the ultimate manifestation of the Anthropocene era, where humans' creations inadvertently become part of the natural world. These spikes, originally designed to deter birds from landing on buildings, have now become a means for magpies to fortify their nests.
The researchers' findings have generated fascination among the scientific community, with praise for their citizen science approach. However, some experts caution that further experimentation and field observations are needed to definitively establish the purpose of the spikes in magpie nests. Zuzanna Jagiełło, an ecologist at the University of Warsaw, believes that the current study is a starting point for deeper exploration of this phenomenon.
Hiemstra has already received reports of other nests incorporating anti-bird spikes, suggesting that this behavior may be more widespread than previously thought. The accumulation of more nests could provide an opportunity to investigate whether the spikes enhance the survival rates of young magpies residing in these uniquely fortified homes.
Despite the scientific significance of the findings, Hiemstra can't help but find humor in the situation. He describes it as "the perfect comeback of the birds," highlighting the irony of birds repurposing anti-bird defenses to protect themselves.