Page:Condor9(2).djvu/21

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Mar., 1907
NESTING WAYS OF THE WESTERN GNATCATCHER
51

the station. I feel that could we have stayed one day longer we should have been able to have seen these nestlings launched upon the world. However, it was of value to know that their departure differed from that of most birds in that they returned to the nest, so many nestlings never going back when once they have left it.

Los Angeles, California.


THE CALIFORNIA DISTRIBUTION OF THE ROADRUNNER (GEOCOCCYX CALIFORNIANUS)

BY JOSEPH GRINNELL

THE extremely limited powers of flight of the roadrunner are partly compensated for by its pedestrial capabilities. So that the range of territory possible to the individual roadrunner is doubtless much greater than one might at first suspect.

Yet I consider this species to be about as permanently "resident" as any bird we have. There may be a slight downward displacement on steep mountain sides in winter. But even if this is homologous to migration the movement must be so limited that we can safely ignore it in a distributional study. We can therefore establish its breeding range as practically coincident with its record area, irrespective of the season of observation.

On the accompanying map, I have plotted all the definite stations of occurrence on record in available ornithological literature. ?Many of the records pertain to counties or other extended areas. For example: "thruout the region;" "all along the Colorado River;" "all along the coast from Morro to Carpenteria," etc. In such cases I have not set down any single station; but the region indicated is of course included in the shaded area on the map. Altho this shaded area may cover some small tracts where the roadrunner does not occur, such as timberlands, swamps and alkali flats, I believe it fairly indicative of the roadrunner's California range.

The species is shy, and may not be seen for days in a region where it is known to be common. There is a sure means of detecting its presence, however, wanting among other birds; and this is the characteristic foot-prints in any soft ground, the dustier the plainer. I have seen these unmistakable tracks (two toes forwards and two backwards) during wagon trips over many parts of southern California. They are all that is necessary to establish the presence of the roadrunner.

The species is most abundant in the San Diegan District (faunal area). It is none the less characteristic thruout the desert regions of southeastern California, tho not so numerous. Its numbers become still less towards the northern limits of its range. It extends sparingly a little ways into the humid coast belt of central California. Mailliard records it as very sparingly resident in Marin County (Condor II, May 1900, p. 63); and there is one record even beyond that, at Sebastopol in Sonoma County (Belding, Land Bds. Pac. Dist., 1890, p. 56). This is the northermost in the coast belt. But in the interior the roadrunner occurs along the foothills at each side of the Sacramento Valley nearly to latitude 41 degrees, this being the