In the first formal treatment of the White-crowned Sparrow in 1772, J. R. Forster described it as an "elegant little species." So many others have found this species to be elegant that Luis Baptista ( Baptista 1989 ) described it as the "best studied songbird" and as one of the best studied of all nongame bird species. Among the characteristics that make this species so attractive to ornithologists are its wide distribution, its abundance over much of its range, and its conspicuousness during most stages of its annual life cycle-all help to make this sparrow an ideal subject for studies of behavior in the wild. In addition, it thrives in captivity on a simple diet.
Because of these traits, much of our understanding of song ontogeny and geographic song variation in birds is based on the study of this species. Particularly well documented are its physiology (endocrinology, hematology, digestion) and breeding and population biology. In almost all fields of study, the most poorly studied subspecies is the nominate Z. l. leucophrys .
Subspecies of the White-crowned Sparrow differ substantially in behavior. Some populations are year-round residents, others are short-distance migrants, and still others migrate thousands of kilometers. In coastal California, this species is multibrooded, whereas at higher altitudes and latitudes, the shorter breeding season restricts it to only one brood.