Page:Which Sex Selects the Nesting Locality - William Henry Mousley - The Auk, 38(3) - P0321-p0328.pdf/3

Vol. XXXVIII 1921 Before proceeding further, however, I should like to mention an interesting case which came under my notice during the summer of 1919, and which seems to bear out my contention that the male does not seek the female, but really waits for her to pass over his chosen area. Now the selected area in this case happened to be the orchard at the side of my house which a Least Flycatcher (Empidonax minimus) had laid claim to. There for several days I heard his oft repeated "che-béc, che-béc," but when a week or more had elapsed and still there were no signs of a female I became interested, and took especial pains to watch his movements more closely. Just about this time a male Warbling Vireo (Vireosylva gilm gilea) also took up a station principally in a large maple tree in front of my house, and two days later was joined by a female. Then came a Baltimore Oriole (Icterus galbula) and selected (more especially) another maple tree on the other side of the road, also in front of my house, and in the course of four days (females here for the past six years have arrived as an average seven days after the males) he likewise was joined by a mate. Now here were three male birds, all in possession of "singing trees" and a certain area of ground, from which all other birds were promptly driven, whenever by any chance they encroached thereon. Two of these birds as we have already seen had not long to wait for mates, but the poor little Least Flycatcher although he persistently kept up his "che-béc" notes all through the summer, never became mated, surely a somewhat striking instance that male birds do not forsake their chosen ground, but await the arrival of a female. Was it otherwise, surely this Least Flycatcher could have found a mate by wandering about promiscuously, in which case having found one, they would be able to keep together until such time as nesting operations commenced, or in case of accidentally losing one another, it would be possible for them to come together again, a somewhat easy thing to do when there is a known station to repair to such as a "singing tree,' or in the case of the Ruffed Grouse a "drumming log." This may partly account for the fact that when birds are robbed of their first, second, or even third set of eggs, they invariably build another nest in close proximity to the old one, as pointed out in my paper "A Study of Subsequent Nestings." They would do so because the ground had become