The Song Sparrow exhibits an enormous amount of geographic variation with over 50 subspecies described. However many of these are probably invalid and most recent authorities recognize about 25. Those in Alaska average very large. This is one of the largest of the Song Sparrow subspecies about the size of a Red-winged Blackbird. This population is similar to M. m. maxima of the Western Aleutians but is grayer overall and has a narrower bill. Canon PowerShot SX50 HS.
References:
Arcese, Peter, Mark K. Sogge, Amy B. Marr and Michael A. Patten.(2002).Song Sparrow (Melospiza melodia), The Birds of North America (P. G. Rodewald, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America: https://birdsna.org/Species-Account/bna/species/sonspa
Rising, J. (2017). Song Sparrow (Melospiza melodia). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/61915 on 8 July 2017).