William Warde Fowler

“ Only in a few cases—namely, in those of the autumn and winter song of a few resident species—are we unable to assign to song a positive importance for the preservation of species or individual. But the caution needed in dealing with these negative instances is well shown by the example of the Crossbill. It is common to quote this bird as an example of abnormal habit in the physiological sense, since it usually pairs and sings in December and January, breeds in February, and hatches its young in March. ”

“ First, as to the general conditions of voicefulness, I think it may be safely said that you will not hear the Song-Thrush in strong wind, nor snow, cold fog, or other uncomfortable wintry weather. What really spurs them to sing is still, open weather, when food is easy to get at: sunshine is not a necessity, and the temperature is of no great account until it becomes really low, and continues so for some days. For example, on March 25th, when I was writing these notes, a bitterly cold day of snowstorms, a Thrush was singing finely at 6.45 p.m., with the thermometer at 26°. ”

“ V. Häcker, of Freiburg-in-Breisgau, in which I found some useful remarks on the autumn and winter singing of birds, which seemed to point to the desirability of further close observation out of doors. I was then living close to the Park at Oxford, and was in the habit of going out daily before breakfast, as well as of crossing the Park two or three times a day on my way to and from college; and I determined to note down each day throughout the winter what birds I heard singing, and especially to record the voicefulness of the Song-Thrush. ”