Chimney Swifts, sometimes called "flying cigars", are rarely seen perching. When not soaring about in the air catching small insects, they cling to the sides of cliffs and buildings. They have long claws and stiff tail feathers that help them achieve their vertical lifestyle. As you can see, they even build their nests on vertical surfaces, usually in caves, tree cavities, or openings in buildings (like the insides of chimneys). They form a half-saucer nest out of twigs using their special sticky saliva to glue everything together. Chimney Swifts lay 1-5 white eggs that hatch in about 19 days. Young swifts are ready to leave the nest in an additional 19 days, after which they will gather in large flocks with other swifts and migrate to South America for the winter. Chimney Swift populations are on the decline throughout their range, however the precise cause is still unknown. You can help Chimney Swifts by constructing an artificial Swift Tower for them to nest in.