It was not until ten years later that enough information had accumulated to warrant an attempt at defining the limits of its range and the periods of its migration. This was done by the painstaking and accurate Wells W. Cooke in the first volume of ‘The Auk,’ in 1884. In this article, ‘Distribution and Migration of _Zonotrichia querula_,’ he was able only in a very general and indefinite way to give the western and southern extent of the range, but the eastern limits remain practically as he defined them.
In 1913 Professor Cooke noted the interesting peculiarity of the migration of the Harris’s Sparrow in the interval that elapses after the first spring advance. He states[11] that the birds become common along the Missouri River in northwestern Iowa soon after the middle of March and yet it is not until early May that they are noted a few miles further north in southeastern South Dakota and southwestern Minnesota. He adds that the dates suggest the probability that these March birds have wintered unnoticed in the thick bushes of the bottomlands not far distant, and have been attracted to the open country by the first warm days of spring. This theory is borne out by the facts as observed by the writer in the Kansas City region. The birds are present in this vicinity during even the most severe winters, but keep to the dense shelter of the Missouri bottoms. During mild and open winters a few scattered flocks may even spend the entire season until spring in the hedges and weed patches of the prairie country.
This Sparrow has always attracted attention in the field by its large size and conspicuously handsome appearance, as well as by its sprightly and vivacious manner and querulous notes, but it has seldom been the subject of special notice in the literature of American birds. Its bibliography is chiefly confined to diagnostic listing in formal works on ornithology, brief annotations in faunal lists, and occasional mention in published field notes.
During the thirty-four years that have elapsed since Prof. Cooke’s article of 1884, the Sparrow, as a migrant, has become well known to ornithologists. Its narrow migration path, the center of which in the United States is approximately down the 96th meridian, has been worked out; the wide extent of territory covered by stragglers has been fully reported;[12] the food habits of the bird while on migration have been thoroughly investigated and the results published;[13] the nest has been seen once,[14] and young just out of the nest have been collected,[15] and the general region of the breeding ground itself is known to be where barren tundra meets the edge of the timber between Hudson Bay and Great Bear Lake. But the eggs yet remain to be discovered.