Rising, J. & Bonan, A. (2019). Old World Buntings (
Emberizidae). 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
https://www.hbw.com/node/52381 on 11 December 2019).
Great point about escaped cagebirds
This point "A problem not often appreciated by cagebird-fanciers is one posed by captive birds that return to the wild. In addition to possible ecological implications, individuals that escape from captivity, or are deliberately released, can cause problems for ornithological records." and what follows is a a very pertinent observation. This merits heavy regulation of the bird trade and ensuring that housing for birds in captivity is doubly secure to prevent escapees as also to ensure their security both from predators like rodents and also a highly probable violent death from escaping outside.