A winter flock of color-marked golden-crowned sparrows was photographed repeatedly while feeding on a gridded 2.44 .times. 1.83 m feeding tray. Each bird tended to return to the same place on the tray, even when no other birds were nearby. Song sparrows and a fox sparrow also showed strong site-tenacity. Mean distance to nearest neighbor was random up to 13 birds on the tray. At higher densities the distance was greater than random (birds over-dispersed). Nearest-neighbor distance was unrelated to sex, conspicuousness of crown markings or size of wing. Each individual maintained a specific inter-bird distance. There was no tendency for the nearest neighbor to be of the opposite sex. Golden-crowned sparrows avoided California thrashers and brown towhees and maintained the same spacing between conspecifics as between themselves and fox sparrows, mourning doves and California quail, but allowed closer spacing with song sparrows. Fox sparrows permitted closer approach by golden-crowned sparrows than by other fox sparrows. Each bird within the flock tended to point in a particular direction and the flock itself was not oriented at random. Nearest neighbors tended to point in the same direction. Site-specificity within a flock may reduce intra-flock aggression.