Colony located just south of the gated entrance to the California Aquaduct off Munz Ranch Road in a narrow draw that extended from the top of the hillside down to Munz Ranch Road and the road into the aquaduct. The primary nest substrate appeared to be stinging nettles. The width of the substrate varied from about 20 feet to about 10 feet in various places along the draw. Surrounding land use was generally high desert scrub, with what appeared to be a small horse ranch located on the east side of Munz Ranch Road. TCBs were observed foraging at this small ranch. Approximate ratio of males to females observed was 8:1, but difficult to estimate because of birds entering and leaving the site.