Spikes positioned on buildings to discourage birds are being utilized by birds to construct nests in a number of places round Europe.
“It appears like a joke,” says Auke-Florian Hiemstra on the Naturalis Biodiversity Heart within the Netherlands. “Nevertheless it’s form of heart-warming that these birds are literally outsmarting us and utilizing anti-bird materials for their very own advantages.”
Birds usually use thorny branches as nest materials, generally inserting them as a roof to beat back predators and shield their younger. In cities, nevertheless, there’s a lack of prickly branches round, so a number of birds have turned to anti-bird spikes.
To date, Hiemstra and his colleagues have noticed this behaviour in carrion crows (Corvus corone) at one web site within the Netherlands and in Eurasian magpies (Pica pica) at websites in Belgium, the Netherlands and Scotland.
In a tree close to a hospital in Antwerp, Belgium, a magpie made a nest containing round 1500 steel spikes. The spikes on the facet of the constructing closest to the tree had been gone, whereas these on the opposite facet had been nonetheless intact. This means that the birds have been ripping the spikes out, versus accumulating unfastened spikes.
The researchers have additionally seen magpie nests with defensive domes containing barbed wire and knitting needles.
They hope to search out out whether or not the spike-laden nests are higher at defending chicks than common ones. “Is there extra breeding success when birds construct nests with the anti-bird spikes? It may very well be doable, however for that now now we have simply too low of quite a lot of observations,” says Hiemstra.
“We actually hope that individuals begin nests extra intently, so we will discover extra of those examples,” he says.
Journal reference: Deinsea