THE ANIMAL FILES

Common swift

Apus apus

A nest made with materials caught in mid-air.

The common swift links an aerial feeding life to a surprisingly precise nesting address.[1]

Follow the evidence ↓
Common swift
Image: Alexis Lours · Commons · CC BY 4.0
The crescent silhouette
Long swept-back wings frame a forked tail.[1]
Building from the air
Saliva binds airborne nesting material.[1]
Food on the wing
Flying insects supply food.[1]

The crescent silhouette

Seen overhead, the very long swept-back wings make a crescent or boomerang outline. The body looks dark, with only a small pale chin patch that can disappear at a distance.[1]

Building from the air

Swifts collect lightweight material in flight and bind it with saliva. Sheltered hollows in buildings, including spaces beneath eaves, provide nesting sites; tree holes and cliffs can also be used.[1]

Food on the wing

Much of a swift's activity takes place aloft, where it catches insects and can drink in flight. Nesting remains an important exception to the airborne routine.[1]

A COMMON MIX-UP

Does an aerial lifestyle mean swifts never use a nest on a solid surface?

No. Swifts breed in sheltered sites such as building hollows, tree holes and cliff crevices.[1]

TRY A LITTLE REASONING

Why would abundant insects not compensate for the loss of every suitable nest hole?

Reveal the explanation

Food and breeding space are different resources. A swift needs a place for its nest as well as opportunities to feed in the air.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Common swift (cited revision)
  2. NCBI Taxonomy — Apus apus

Last fact check: