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 May, I9O 7 THE BREEDING BIRDS OF ESCONDIDO 8 5 there is a more or less thick growth of willows, in some places forming fine large groves with many large cottonwoods and a few sycamores. This is a bird paradise and much of my huntig and collecting has been done here. At Crescent Valley there are some fine oak groves and the hillsides are still pretty well covered with trees. There are many large cactus patches. on the south slopes and the hillsides and small ravines are well filled with sage, grease-wood, sumac and wild lilac. Bernardo boasts of one tule pond, San Pasqual of two, and there are several water holes along the river, which may run well into July, or not at all, according to the seasoh's rains. For two successive years one San Pasqual pond and the Bernardo pond were dry. In-1906 the San Pasqual pond had five feet of water in the tule patch and the river was running until August. The average rainfall here is about fourteen inches. The following list comprises all the birds known to have nested in this section and is the result of observations covering some sixteen years. Most of the species given are regular breeders, some very common, others rare but regular, a few casual only. Almost all, however, nest here in such sufficient numbers as to be consid- ered fairly .common in consideration of the comparatively limited territory suitable to their requirements. In some few instauces there has been considerable difference in relative abundmme, traceable without doubt to the character of the preceding winter; but in most cases the number of nesting birds remains apparently uniform. In the nest- ing seasons following several very dry winters previous to 1905 one of the corn ~ toonest birds along the river in San Pasqual was the willow goldfinch, while the lazuli bunting was comparatively rare. In the season of 1905, after a winter of more than the average rainfall, the goldfinch was noticeably wanting and in 1906, after a very wet winte'r, it was hard to find them at all. In 1905 the lazuli bunt- ing was everywhere, as common, almost, as the house finch, but was not at all com- mon in 1906. In 1906, the lawrence goldfinch was more plentiful than I had ever seen it, and the Arkansas goldfinch was nesting in the orchards and willows in great abundance. Previous to 1905, the long-eared owl was a very common bird in the willow groves along the river; but since then they have been noticeably absent, and the nest complements, previously four or five, are largely of three eggs only. These birds were seldom disturbed and it is rather hard to account for their dinfinished numbers on any other ground than that the wet seasons caused the destruction of the various small mammals on which they so largely feed, causing them to migrate to better hunting grounds. I am very well convinced that most of our resident birds produce and bring to maturity two broods in a season, some even more. With the Raptores one brood is a rule unless the first clutch of eggs is taken when a second is always laid. The Iong-eared owl, however, and possibly the burrowing owl will often raise two broods. Of the other birds the California shrike, western mockingbird, mourning dove, house finch, black-chinned hummingbird, and probably the Anthony towhee and western lark sparrow will raise three broods under favorable conditiom. The two former species I have known to do so iu my own orchard, the types of eggs being the same in every case. In the following list the dates given are for the earliest and latest nesting dates, the eggs showing very slight or no traces of incubation unless otherwise stated. I am greatly indebted to Messrs. N. K. and B. P. Carpenter for the use of their field and msting notes which have aided me materially in compiling the list. C01ymbus nigric011is calif0rnicus. American Eared Grebe. A very rare breed-