Andalusian Chicken

Andalusian Chicken is a Spanish breed native to the Andalusia region of southwestern Spain, particularly the area around Utrera, best known internationally in its Blue Andalusian form. Blue birds from Andalusia were imported into England no later than 1851, where English breeders developed the internationally recognized blue-laced variety through selective and cross-breeding. The slate-blue coloring is produced by a dilution gene acting on the gene for black plumage, following simple Mendelian inheritance: two copies of the dilution gene produce an off-white bird, no copies produce a black bird, and one copy produces the characteristic blue, so a blue-bred flock always also throws black and off-white chicks alongside blue ones in a fixed ratio. Hens are solid producers of large white eggs, laying around 165 a year, with the largest eggs coming from the off-white variety bred from blue parents. The breed has become seriously endangered, its Spanish population estimated at about 10,000 birds in 2009 and its worldwide population down to roughly 623 birds across six countries by 2025, with Germany listing it as extremely endangered.