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 26 THE CONDOR VoL XV GENERAL DISTRIBUTION OF TItE BAND-TAILED PIGEON There has been more or less confusion in the popular mind as to the dis- tinctness of the Passenger Pigeon from the Band-tailed Pigeon. Both have been called Wild Pigeon. The two species, however, are very different, and as far as known the ranges of the two nowhere overlapped. The Passenger Pigeon (Ecto- pistes migratorits) was restricted to the region east of the east base of the Rocky Mountains; the Band-tailed Pigeon (Columba fasciata) ranges from, and includ- ing, the Rocky Mountains westward to the Pacific 'Coast, though not of course continuously over the intervening desert areas. Recorded localities of occurrence of the Band-tailed Pigeon extend as far east as Boulder County, Colorado, and western Texas, south into Mexico, and north to Vancouver Island and the adjaeem mainland of British Columbia. Rela- tively few of these localities, however, are breeding places; many are of sporadic occurrences. So that the area outlined must not for a moment be thought of as supporting a pigeon population throughout its extent, either continucxusly or regularly. In a general way it may be said that at the north and at high altitudes the species is only a summer visitant. To be more explicit, the Band-tailed Pigeon summers in the Transition life zone, whether this be in the northern part of its range or at the south. In the latter case the high altitudes of the mountain ranges resorted to, result in the same temperature conditions as at lower levels to the northward. In winter the pigeon migrates to more southerly latitudes, or to lower alti- tudes, as the conditions make it necessary in order to reach a bearable winter cli- mate. Although recorded sot:th along the Mexican Plateau, it is believed that practically all the birds breeding to the north of the Mexican bcundary winter within the United States, concentrating at that season in the extreme southwest. From the data at hand per{aining to distribution, it seems probable that the pigeons of the Rockv Mountain region do hot cross in migration to the Pacific slope, but xvinter wit the locally bred cr',ntingent in suitahle places near the Mex- ican line, in Arizona and New Mexico. In parallel fashion those pigeons ap- pearing in the valleys of California in winter COlTIe from the mountains adjacent and from the Pacific Coast district to the north, in Oregon, Washington and Brit- ish Columbia. 'LOCAL DISTRIBUTION The following facts bear upon the question of the source of at least part of the pigeons wintering in the valleys of California. The species occurs at Blaine, Washington (near the British Columbia boundary), from May 5 to Sep- tember 15 (Dawson, I9O9, p. 555); in southern Washington west of the Cascades it is present from May 15 to September (Coues, I874, p. 386); and at the mouth of the Columbia River it'is present from Miy to October (Bendire, I892, p. i22). In Washington County, Oregon, it is common in summer (Anthony, in Bendire, I892, p. I23)'; at Dayton, Yamhill County, O[egon, the pigeon arrives April 2o and leaves the last of November (Hadley. in Woodcock, I9O2, p. 28); at Cor- vallis, Benton County, Oregon, it octtits rom the first of April until the last cf September (Woodcock, I9O2, p. 28. From the above data it will be seen that north of the northern boundary of California the Band-tailed Pigeon is wholly migratory. It seems inevitable that this northern bred contingent moves south ito Califoriia for the winter season. In other words the entire pigeon population of the' Pacific Coast region concen-