Formerly treated as a race of the slighly larger Asian Azure-winged Magpie (Cyanopica cyanus), which breeds over a large area in eastern Asia, the Iberian Azure-winged Magpie (Cyanopica cooki ) is among our most beloved resident birds and one of the four endemic bird species of the Iberian Peninsula. Within its breeding range, the core distribution lays on the southwest, although observations of flocks during the past few years in other areas far from its regular breeding range – as far as Alicante by the mediterranean coast of Spain – suggest a possible expansion of the species.
So, why almost identical bird species occur so far apart from each other?
One hypotesis suggest that during the glaciation of the Northern Hemisphere approximatelly 2.6 million years ago in the Quaternary period, a primitive population of Azure-winged magpies with a wider range was split by ice sheets into two sectors at both extremes of Eurasia where conditions were not as severe. These sectors have remained without contact until present, resulting in two different species.
The Iberian Azure-winged Magpie is a gregarios species, therefore all its activities are performed in groups. Huge flocks of up to 300 individuals outside the breeding season have been observed. It inhabits open woodlands, in particular iberian Holm Oak (Quercus ilex) dehesas and Stone Pine (Pinus pinea) woods, where its population is increasing with average densities of 31-80 birds/km².
It is an oportunistic species and hence it exploits a big array of resources acting as an efficient natural biological control limiting the expansion of forest insects as the Green Oak Moth (Tortrix viridana) or the Gypsy Moth (Lymantria dispar).
– De Juana, E. & García, E. 2015. The birds of the Iberian Penísula. Christopher Helm. London
– Pujol, J.A & Sáez, A. 2014. Quercus, 344: 48-49