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 Spring Migration of 1896 in the San Gabriel Valley.

WING to the mild winter of 1895-96, the spring migration was somewhat earlier in than usual. Beginning in the latter part of February with the arrival of flocks of Violet-green Swallows, the migration promised to be at its height before the middle of April. But on March 2 and 3 it was suddenly checked by severe snow storms in the mountains and cold weather in the valley.

The cold weather not only proved be a check to the northward migration, but it cut off the food supply of birds, which had not been seen or only recorded in small numbers during the winter, and compelled them to move southward out of the mountains into the warmer valleys nearer the coast. The most noticeable example of this was the Band-tailed Pigeon. This species had not been seen in the valley during the winter, but immediately after the storm large flocks of them were noticed in the grain-fields and oaks of the valley. The mountain Bluebird had before March 3 been noticed once or twice during the winter; but in the two weeks following March 3 it was common. Among other species whose numbers in the valley were considerably increased by the effects of the storm were the Californian Woodpecker, and Golden-crowned Sparrow, Lincoln's Sparrow, Thurber's Junco, Cedar Waxwing, and Western Robin.

The Swallows which had so early ventured upon their northward journey were caught in rough weather. A number were seen on March 3 flying wildly in the pouring rain. However, the quick return of warm and pleasant weather cleared the valley of a large number of winter visitants and by March 10 the swallows had again taken up their course through the valley from southeast to northwest, breaking the wind, as it were, for the great multitude which was to follow.

Before the end of March the northward migration was well under way; Band-tailed Pigeons, Sharp-shinned of Hawks, Red-naped and Red-breasted Sapsuckers, Lewis' Woodpeckers and American Pipits had disappeared on their northward journey; while Say's Phœbes and Vermilion Flycatchers had left the valleys of the coast for their breeding homes on the east side of the mountains. But to fill the vacancies made by these departures there had arrived from the south Texan Nighthawks, Costa's and Rufous Hummers, to Arkansas Kingbirds, Bullock's and Arizona Hooded Orioles, Cliff Swallows, and others.

The number of arrivals and departures each day was increasing, and by the last two weeks in April the northward movement was at its height. Most of the migrants were moving northwest, parallel to the mountain ranges.

About April 4 the last Cassin's Kingbirds were seen; on the same date the Ash-throated Flycatcher was first noted in Eaton's Arroyo. The Black-chinned Hummingbird, Western and Hammond's Flycatchers, Black-chinned Sparrow, Green-tailed Towhee, Black-headed Grosbeak, Lazuli Bunting, Warbling and Cassin's Vireos, Calaveras, Yellow, Black-throated Gray, Macgillivray's and Pileolated Warblers, Russet-backed Thrush were present in numbers before April 15. Before this date Lutescent Warblers and Western Yellowthroats had increased their numbers over winter residents to a large extent. California Purple Finches and Ruby-crowned Kinglets had left the valley.

The migration was fast reaching its height; still, a number of summer residents and transients had not arrived. April 25 showed the presence of more species than had hitherto been noticed; over sixty different species were recorded within the radius of 1½ miles from the mouth of Arroyo Seco outside the mountains. Warblers, sparrows and flycatchers were especially abundant. The new arrivals were the Belted Kingfisher, Olive-sided Flycatcher,