278 ANIMAL LIFE IN THE YO SEMITE 



probably has also had a marked effect on the number of pigeons visiting 

 the Yosemite Valley from year to year. Fluctuations for such reasons 

 make it difficult to determine with accuracy to what extent the birds have 

 actually been reduced in numbers in the region. 



Western Mourning Dove. Zenaidura macroura marginella (Woodhouse) 



Field characters. — Much smaller than domestic pigeon, and with a pointed, white- 

 margined tail ; upper surface olive brown, breast pale brown. Wings produce a whistling 

 sound, loudest as bird takes flight. Flight, when fully under way, swift and direct, 

 with regular and sweeping wing strokes. Voice : A series of four mellow yet far-reaching 

 notes, ahcoo', roo coo, repeated at rather long intervals. 



Occurrence. — Abundant resident in the western lowlands and foothills (Lower and 

 Upper Sonoran zones), ranging in summer locally into lower part of Transition Zone. 

 Twice observed in Yosemite Valley (May 28, 1911, and September 24, 1915), once at 

 Hazel Green, 5600 feet altitude (May 14, 1919), and once at 10,300 feet altitude near 

 Vogelsang Lake, September 4, 1915 (single birds in each instance). Found also east 

 of the Sierras (where likely only a summer visitant), in Mono Basin and thence west 

 to Walker Lake. Partial to open situations; to be seen usually in pairs, or, in fall, 

 winter, and early spring, in flocks numbering up to fifty or even more individuals. 



The Western Mourning Dove is to be seen in numbers over the western 

 lowlands at all seasons of the year. On almost every trip we made by train 

 from Merced into the mountains we saw these birds flying over the adjacent 

 fields, often flushing at the side of the railroad and keeping abreast of 

 the train for a time as it traveled twenty or more miles an hour. In all 

 of the foothill country doves are to be looked for as of regular occurrence. 

 Near Lagrange they were about continually, visiting the river margin to 

 drink or resting momentarily on the boulder heaps nearby. At Blacks 

 Creek near Coulterville they came down to drink at the creek every 

 evening at early dusk. In Yosemite Valley doves occur only as stragglers. 

 In our own experience, as noted above, but 2 lone birds were recorded 

 there. 



The breeding season extends from April or May well through the 

 summer. Nests are to be looked for in a variety of situations. We found 

 4. One noted near Snelling on May 28, 1915, was situated 8 feet above 

 the ground in a blue oak. It contained one egg. On the meadows east of 

 Coulterville, at an elevation of 3200 feet, 2 nests were discovered on 

 June 7, 1915. They were both situated on the slanting side of a small 

 gulley that ran through the meadow. One contained 2 eggs and the other, 

 one. On June 8, 1916, in Mono Basin, east of Mono Mills, at an altitude 

 of 8400 feet, a dove was seen incubating 2 eggs in a nest situated on the 

 bare ground at the side of a sagebush. 



After the broods are reared, old and young doves combine into flocks 

 and then range far and wide in search of ripening flower and weed seeds, 



