Common Swift in Northamptonshire

Common Swift Apus apus defecating.

With close observation the moment of defecation can be predicted as the whole process takes several seconds. The feathers of the vent area reform and the cloaca extends through the opening before defecation so that the under-tail coverts and tail feathers are not soiled.

Yardley Hastings, Northamptonshire. UK
July 2006