Swallow Notes from Fresno County, California
Swallow Notes from Fresno County, California
Mr. Grinnell's record in THE CONDOR for May-June of a pair of Barn Swallows observed near Fresno on March 15 last, has caused me to put the following notes on record.
On the morning of March 19, 1905 the writer observed a single Barn Swallow (Hirundo erythrogaster) in company with several Tree Swallows circling about a pond some six miles north of Fresno. As it was the first one seen that spring it seemed probable that the bird had reached this place from some point to the north of us. My suspicions were partly confirmed during the fall of the same year when the Barn Swallows apparently departed toward the north. September 25 large numbers of them passed over at frequent intervals all day. They certainly appeared to be migrating but were travelling in a course directly opposite to that which they would be expected to pursue at that time of year. The following spring I had an excellent opportunity to watch for the first migrant, and was not greatly surprised on the morning of March 19, upon hearing a cheerful twittering overhead, to see a Barn Swallow travelling southward at a considerable height.
Is it possible that this swallow has two routes by which it enters this part of the San Joaquin Valley? Possibly in certain seasons the usual southern way is undesirable from some cause, and the birds enter the valley by a northern route. It would be interesting to learn from observers living north of Fresno, the dates upon which this swallow was first observed for the spring of 1906.
In Fresno County the Barn Swallows nest, almost without exception, under bridges, fastening their nests to the stringers over the water. The smaller bridges over all the irrigation ditches shelter from one to three or four pairs, while the species swarms by hundreds under the large ones that span some of the sloughs.
The Tree Swallow (Iridoprocne bicolor) is present in small numbers throughout the winter, but each year during January and February, I have observed a southward movement on the part of this species. Sometimes a single bird passes over but often two or three are seen together. The Tree Swallow has been found nesting in sycamores along the San Joaquin river and in pine stubs at Shaver Lake.
On March 28, 1908 the writer found a pair of Violet-green Swallows (Tachycineta thalassina lepida) busily engaged in carrying nesting material into a cavity in a sycamore stub near the river about nine miles north of Fresno. Several other pairs were discussing the fitness of other cavities. This, I think, is rather early nesting.
My earliest record for the arrival of the Cliff Swallow (Petrochelidon lunifrons) is March 14 (1903 and 1904). A nesting colony was examined April 29, 1910 in which a number of nests held good sized young birds.
