Common Swift (apus apus) Unique breeding behaviour.

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This nesting site was particularly interesting because all the nests along the full length of 3 terraced houses could be accessed by the incubating birds in the adjacent nest. I witnessed 'egg swapping'. One morning there may have been 3 eggs in one nest and 2 in the next nest, next morning the 3 egg nest would have 2 eggs and the 2 egg nest would have 3. This behaviour happened along the full length of the of the roof space and all the nests. There were about 30 nests altogether and this behaviour had no detrimental effect on hatching as they all laid eggs at about the same time.

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Size: 11242px × 5088px
Location: uk covenham lincolnshire
Photo credit: © fotolincs / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: apus, biodiversity, birdwatching, eaves., hadg, nest, nesting, roof, space, swift.