Adults are black and have the largest of the swift’s in BC. They have a streamlined body with long narrow wings. Black Swifts nest in forested areas along rivers, choosing to nest behind waterfalls or other damp cliffs that are inaccessible to predators. They lay one egg and take turns incubating for up to four weeks. They rear one young per year. They forage on flying insects exclusively. Nests may be reused year after year.