Mrs. Mallard’s condition looks to be a case of “leucism.” Massachusetts State Ornithologist Andrew Vitz describes the condition in MassWildlife issue No.1 2014 where he identifies a robin pictured, and sent in by a reader, as being a “leucistic bird: one that due to a genetic aberration, lacks melanin pigment in some if its plumage.” He writes: “This is a much more common phenomenon than true albinism, a rare situation where there is no pigment anywhere in the skin, plumage, or iris of the eyes. Leucism typically affects only a portion of the plumage, and even then, yellow pigments are not affected. ”
The British Trust for Ornithology furthers that “leucistic birds, affected plumage lacks melanin pigment due to the cells responsible for melanin production being absent. This results in white feathers, unless the normal plumage colour also comprises carotenoids (e.g. yellows), which remain unaffected by the condition. Although leucism is inherited, the extent and positioning of the white colouration can vary between adults and their young, and can also skip generations if leucistic genes are recessive.
The reduction of pigment in leucistic birds causes feathers to weaken and be more prone to wear. In some situations this can hinder flight, which, in addition to leucistic birds usually being more conspicuous, can heighten risk of predation. There is also evidence that leucistic birds might, on occasion, not be recognized or accepted by a potential mate.”
Here on Manchaug Pond, a similar bird was reported in August of 2010. Mrs. Mallard in her younger days? Family of Mrs. Mallard? Don’t know, but Mrs. Mallard can be seen with the Mister in Holbrook’s Cove.
If you would like to purchase a photo of this special bird, let us know the size you would like as we will be ordering and offering in our new website store! And be sure to send in your photos and stories of Manchaug Pond, we’ll try to publish them all!