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 Mar., 1915 ADAPTABILITY IN THE CHOICE OF NESTING SITES trees, while in the lower valley, where because of the alfalfa and other culti- vated crops food is as abundant as in the older sections, the Kingbirds, in spite of the lack of the usual nestlug sites, patrol the alfalfa fields for food, but are compelled to use the hay-derricks an,i telephone poles for nesting purposes. Because telephone poles are as abundant as ever in the older sections, and be- cause the poles are practically deserted as soon as the trees become large enough to offer suitable sites, one would infer that the use of a pole for nesting vas only a temporary expedient. Almost all my observations were made during the season of 1912, my l-line during 1913 being entirely occupied with other vork. Perhaps the ollowing list with the accompanying remarks will show best the. habits of this bird. June, 19ll. A pair built a nest at the base of the lowest horizontai limb of a five-year-old cottonwood in my door yard. No larger trees werc xvithin two miles of this. The nest which contained three fresh eggs was blown out June 3. June, 1911. Nest on arm of electric pole in front of my home. Nest blovn out June 28, 1911, probably containing eggs at the time. June, 1911. Nest in hay-derrick on a neighbor's ranch destroyed June 28 during haying; contained young. June 23, 1912. This day was devoted to a trip twelve miles up the valley to Granger, going on the Outlook road and returning on the hill road, with the sole object of locating Kingbird nests. These were easily located because of the open country and the noisy restless habits of the adult birds, which stay at some high outlook point near the nest and keep up a constant chattering. The first part of this trip was along the electric line between my ranch and Sunnyside. This is a section which has been under extensive irrigation .for less than ten 'years, and as stated previously, contained no trees large enough to suit Kingbirds. In the two miles of this line were six Kingbird nests, always next the pole, and variously placed on ttl,. cross 'arm, behind a converter, or even balanced behind a wire bracket. On%f these nests was of the Eastern Kingbird ( Tyrannus tyrannus) '' Observations at this time and on folloving days indicated that these nests contained at this date either eggs in advanced incubation or young birds. One of these nests blew dovn during a vind in the middle of July a few days after the young birds had left. The next part of the trip followed the electric line from Sunnyside through Outlook to Granger. This low strip was one of the earliest irrigated sections, and now Contains many windbreaks of lombardy poplars and black locusts. No nests were seen on poles until within two miles of Granger, where near Lib- erty the ground is higher, more rolling and has fewer vind breaks. Here vere two poles each with a few straws hanging on its arm, the wreck of a nest blown down during a gale of the previous week. The other nests along this road were as follows: In the open country east of Outlook the nest shovn in figure 19 was found on the top of a hay-derrick. The old nest in the same box showed that it had been used similarly the previous season. Three pairs of birds were seen near Outlook, the nests of which remained undiscovered. Tvo were in poplar windbreaks. .An Eastern Kingbird's nest was found tventy feet up in a black locust east of Outlook. This nest, contrary to the habits of the Arkansas Kingbird, was well concealed by foliage. Thirteen other nests were seen, six in poplars, two in black locusts, three in hay-derricks, each of vhich stood in a large alfalfa field and each of which had been destroyed dur-