- Black above, black-and-white below, with long, forked tail. 6-7″
- A shrill, excited jejejejejeje in descending scale.
- Flying insects.
- A saliva-glued bracket in crevice in cliff. 3-6 white eggs.
- Open sky; cruising widely. Breeds mainly in dry mountains and canyons.
- Interior valleys from British Columbia through the Rocky Mountins and the southwest including California.
- Moves south in winter.