Common Swift or Chimney Swift?
Here's how to tell the difference
Common Swift
Chimney Swift
Common Swift
Apus apus
Common Swift Identification Guide
General appearance: The Common Swift, scientifically known as Apus apus, is primarily recognized by its long, slender, sickle-shaped wings and streamlined body. Its plumage is typically dark sooty brown, which often appears black when viewed against the sky. The bird's throat is slightly lighter, providing a subtle contrast to its overall somber coloring. With a short tail and a broad, slightly forked appearance, the Common Swift exhibits a sleek and aerodynamic figure optimized for fast, agile flight. Male vs female: The Common Swift exhibits minimal sexual dimorphism, meaning males and females look remarkably similar. Both sexes share the same size, wing shape, and coloration, making them difficult to differentiate unless observed under specific conditions such as behavioral patterns during the breeding season. Juvenile: Juvenile Common Swifts resemble adults but are often distinguishable by their slightly duller plumage. Their feathers may not have the same glossy sheen as those of mature birds. Additionally, juveniles may have pale edgings to their feathers, which gives them a slightly scaly appearance. This scaly pattern can help in differentiating younger birds from fully matured adults, particularly when observed in mixed-age flocks.
Size
6.3 - 6.7 in/1.1 - 1.8 oz
There's more to learn about Common Swift
View full detailsChimney Swift
Chaetura pelagica
General appearance
Chimney Swifts are small, dark birds with slender, curved wings and a cigar-shaped body. Their plumage is generally sooty gray-brown with a slightly paler throat. Their short, stubby tails make them distinctive in flight, resembling a flying cigar. They are often seen in rapid, fluttering flight, with swift, jerky movements.
Male vs female
Chimney Swifts show little sexual dimorphism; males and females look similar and are difficult to distinguish in the field based on appearance alone. Both sexes have comparable coloration and physical traits, which is common among swifts due to their aerial lifestyle.
Juvenile
Juvenile Chimney Swifts resemble adults but may have slightly paler plumage and a softer, duller appearance. They exhibit the same flight pattern but may appear less adept at maneuvering. Over time, juveniles acquire the darker, more uniform feathering seen in adults.
Size
4.7 - 5.9 in/0.6 - 1.1 oz
There's more to learn about Chimney Swift
View full detailsHow to tell the Common Swift from the Chimney Swift
Visual differences
The Common Swift (Apus apus) and Chimney Swift (Chaetura pelagica) display notable visual differences. The Common Swift is larger, with a length of 6.3-6.7 inches and a weight of 1.1-1.8 ounces, compared to the Chimney Swift's 4.7-5.9 inches and 0.6-1.1 ounces. Common Swifts have uniformly dark plumage, while Chimney Swifts are sooty gray-brown with a paler throat. Chimney Swifts have distinctive crescent-shaped wings and short, stubby tails, in contrast to the Common Swift's streamlined appearance.
Key differences and behavior
Common Swifts (Apus apus) and Chimney Swifts (Chaetura pelagica) share aerial lifestyles but exhibit distinct behaviors. Common Swifts are mostly found across Europe and Asia, favoring urban and temperate regions, while Chimney Swifts inhabit eastern North America, nesting in chimneys or hollow trees. Common Swifts form "screaming parties" as social and courtship displays and are monogamous, returning to the same nesting sites annually. Chimney Swifts engage in aerial chases, forming lifelong bonds and constructing nest structures with twigs and saliva. Dietarily, both species consume flying insects, but Common Swifts also feed on airborne spiders and rely heavily on urban insect abundance. Chimney Swifts target varied insects and adapt to denser insect areas. Breeding involves shared incubation and feeding across both species. Notable size differences exist, with Common Swifts being larger, weighing 1.1-1.8 oz and measuring 6.3-6.7 inches, whereas Chimney Swifts are lighter at 0.6-1.1 oz and shorter at 4.7-5.9 inches.
Common Swift vs [Select a bird]
[Select a bird]
Pick a bird to compare
Chimney Swift vs [Select a bird]
[Select a bird]
Pick a bird to compare