**Description:** Often called a "cigar with wings," these soot-gray birds have a slender body and long, narrow, curved wings.
**Size & Weight:** 4.7–5.9 inches long. Weighs 0.7–1.1 oz.
**Behavior:** They spend almost their entire lives in the air and use sticky saliva to glue tiny twig nests to the inside of chimneys or hollow trees.
**Identification:** Look for rapid, erratic wingbeats and the lack of a visible tail. They make a constant, high-pitched chipping sound.
**Habitat:** Forage over the forest canopy and reservoir; nest in vertical shafts.