Page:Condor20(1).djvu/18

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Jan., 1918
EARLY AUTUMN BIRDS IN YOSEMITE VALLEY
17

finny prey under the clear water—and it really did look a bit like a clumsy fish as viewed from the rocks above the water’s level. This bird would come so close to shore as to enable one to see with the naked eye that the bill was depressed (that is, broader than high) instead of compressed, thus identifying it as the Eared Grebe. When first seen, August 21, there were just about enough of the remnants of the nuptial plumage, a few of the yellow silky feathers on the side of the head still extending far below the level of the eye, to determine the species at close range without the aid of the bill. Some of the younger tourists amused themselves by throwing bits of rock at the bird—which they did not hit! Before the missiles neared their mark it was performing submarine evolutions in plain view of its audience. This grebe was seen a few days later on, but apparently left Mirror Lake early in September.

An effort was made to note the times of departure of some of the summer visitants, but the sudden absence of a bird is much more difficult to determine than its presence. The Calaveras Warbler (Vermivora ruficapilla gutturalis) breeds in the valley, but was scarce at the end of August. It was also difficult to distinguish in the bushes and trees from the immature Macgillivray Warbler (Oporornis tolmet) and from the Lutescent Warbler. The last specimen taken of the Calaveras Warbler was on September 16, and the last bird was seen on September 26, of which latter there was some slight doubt as to identification.

The Lutescent Warbler was first seen September 18, after which its numbers increased slowly until the 26th when a small wave of migration reached the valley, the eastern end of Sequoia Lane being especially popular as a feeding and resting place. While no attempt at estimating their numbers was made, they were in evidence all around the observer, probably seventy-five being noted that morning. The next day, however, a tramp over the same ground showed but few individuals remaining, not a dozen being seen during the whole day. On the morning of the 29th, the day the writer left the valley, four were seen, so some were still there.

A close watch was constantly kept up for anything new, but it was not always possible to identify everything that was caught sight of. For instance, near noon of September 14, two sparrows, apparently Passerculus, were seen to fly out of the meadow grass into a small willow bush near the bank of the river just below Yosemite Village, but diligent search failed to bring them into view again. But one Passerculus was taken, and this was on September 27, in the willows still farther down river. It proved to be Passerculus sandwichensis nevadensis, Nevada Savannah Sparrow, evidently a wanderer from the east side of the mountains. No other Savannah Sparrows were noted.

Another wanderer was a Brewer Sparrow (Spizella breweri) which was taken among some Western Chipping Sparrows. There may have been more of these about, but it was impossible to pick them out among the latter.

The Lincoln Sparrow (Melospiza lincolni lincolni) has been recorded from the valley, but it was rather a surprise to find there the Forbush Sparrow (Melospiza lincolni striata) also, a bird associated with the humid coast belt as a winter visitant. Two of these were taken, one on September 15 and the other on the 18th.

Along the river are ideal spots for song sparrows, yet but three were seen during the six weeks of observation, and only one taken, on September 27, which proved to be a visitor from the eastern side, this form having been described from Honey Lake under the name Melospiza melodia fisherella, by Oberholser (Proc. Biol. Soc. Wash., xxiv, December, 1911, p. 251).