Mountain Bluebirds Hovering
Mountain Bluebirds Hovering
While hunting jack rabbits at Cannon, Solano County, California, on February 13, 1939, I was much interested to observe Mountain Bluebirds (Sialia currucoides) hovering in the air in one spot in such manner as do Sparrow Hawks and White-tailed Kites. From fifteen to eighteen birds thus hovered at one time, legs dangling, tail spread and pointing downwards, and eyes searching the ground below. They were of course feeding and appeared successful in recovering their prey at each drop to the ground. These drops were from elevations of from ten to fifteen feet. They were not rapid plunges or dives such as made by hawks or falcons, but gentle flutters to the ground, where they alighted and snatched the prey with the bill.
Being inquisitive as to what attracted these birds, I took one specimen and found in the stomach three whole black ground beetles (Amara insignis) and a cricket (Gryllus assimilis). There were also many fragments representing other individuals of these same species, and segments of other beetles, mostly Carabidae, and of orthopterans. These insect identifications were made by E. Gorton Linsley of the Division of Entomology, University of California.
Emerson A. Stoner
Benicia, California, March 22, 1939
