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 May, 1914 A CHANGE IN FAUNA 121 with all the original inhabitants. The hawks, being wandering in their habits, are still found here, and are even more abundant than formerly. The Brewer Sparrow, originally nesting in dense-leaved sage-brush, is now more common than formerly, and builds its nests in fence corners or weed patches. Last summer I observed something interesting about this bird. When it built in sage-brush, the eggs were dark blue, almost as dark as a Cat- bird's, but were normal in size and markings. The last nest I found was in an alfalfa field in a slight depression. The nest was constructed the same as previously, but the eggs were normal in color as well as in size and markings. I am very much interested to learn if the whole species will make this change, or whether it was merely a variation restricted to the individual bird. As soon as grain and alfalfa were raised, many new birds became com- mon, such as the Grasshopper Sparrow, Lark Sparrow, White-rumped Shrike, and the 1VIountain and 1VIerrill Song Sparrows. Field mice, meanwhile, had become a pest, and in 1910 there was a great influx of Short-cared Owls. They remained.throughout 1911, but are now only fairly common, since the mice have been very. much thinned out. After two years of irrigation, the loose sandy soil became saturated with what was called "sub-water". Low places became wet meadows or even ponds, the low land filled with growths of willows and weeds, and the ponds with cat-tails. Now was there, indeed, a host of new arrivals. Tule Wrens, coots, ducks, bitterns, black-birds, rails and killdeer are now very abundant, whereas formerly there were 'none. The water birds, or waer-loving birds, are now more plentiful than the others. During migrations there are vast numbers that visit us for a month or more. These migratory birds have always passed over the project, or, if they stopped at all, did so along the river only. Trees are scarcely large enough for birds to build in yet, but the orchards and hedges are frequented by robins, grosbeaks, orioles, and warblers. I once saw a Red-breasted Nuthatch, and wondered how it could get along in a sage- brush region. The Burrowing Owl, badger, and kangaroo rat were forced to find high ground when the sub-water came up. Horned toads and lizards re- treated when the land was tilled. Rabbits are a pest only to the farmers who live near large areas of uncleareal land. The Pinyon Jay inhabits the foothill region several miles away, and makes Occasional visits. The Sparrow Hawk is becoming common, coming from an old settled area thirty miles away. The river belt has changed but little. The villows have been the home of robins, warblers, and sparrows; while swallows, kingfishers, and flickers nest in the banks. There are many water birds that breed on the brushy is- lands in the stream. There are no new waterbirds found there, but many birds such as the Lark Sparrow, Grasshopper Spa;row, and Kingbird, have come from the inland territory. The Valley Partridge (introduced from California) and Belted King- fisher have spread over the highlands of the project. The same is true of many kinds of ducks and the Limicolae. At the dam there are other conditions prevailing. Here a large colony of Cliff Swallows nests under the caves of the power plant, over the roaring water. In the heaps of rocks excavated from the canals there are several pairs of Rock Wrens, of interest because this is the only place hereabouts where they are found. Of course this is local, as the changes in the whole pro-