A reader spotted a bird with albinism. The Geneva wildlife inspector explains why this type of mutation is uncommon.
“I’m sure it was a blackbird, but it was white. His song was characteristic, and he was surrounded by common blackbirds.” Saturday around 2 p.m., José’s sharp eye spotted the astonishing bird in Lancy, near the Bachet and the traffic police. His observations turned out to be correct: Gottlieb Dandliker, the cantonal wildlife warden, to whom his photos were submitted, confirmed on Monday that it was indeed a blackbird, probably a male, affected by a phenomenon of albinism.
A genetic disadvantage
“Such an observation is rare, even very rare,” he says. Albinism exists in many birds, but not only: in the biopark lives a white walibi, for example. The rarity of these birds is explained by the fact that, in nature, they accumulate disadvantages: “They are badly camouflaged, when a predator attacks a group, it concentrates on the animal which is different, and the difference does not please not females.
Therefore, the white blackbird does not spread: it dies young and fails to reproduce. “But as albinism is a recessive gene, it can be found in his brother” who, apparently ordinary, has a better chance of surviving and mating. The wildlife warden also notes that such an animal is much rarer in the wild than in urban areas, where there are fewer predators.
Five cases per year
He considers the blackbird photographed by José “really magnificent”, not all of them having so many white feathers. And he insists on the exceptional nature of the phenomenon. “I myself have only seen four or five in my life, while several thousand blackbirds live in Geneva. If I started looking for one, it would probably take me several years to find it. At the end of the lake, some five cases per year are listed on average. Thus Gottlieb Dandliker found three other specimens adorned with white photographed in the canton for a year, on a site dedicated to wildlife observation.