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Illustration of a White-naped Swift (Streptoprocne semicollaris) egg, 27.8 × 18.3 mm
Illustration © 2026 Lincoln Savi, Savi Made. Free to use with credit.

Streptoprocne semicollaris

  • 27.8 × 18.3 mm (estimated)
  • Speculative: we haven't found documented measurements of this egg yet, so we estimated its size from related birds.
  • Clutch: 2 eggs
Breeds in Mexico

White, unmarked (clutch of two laid on sand in caves).

Sources of information

Size
Marín, M. 2016. Breeding biology and natural history notes for White-collared Swift Streptoprocne zonaris in Costa Rica. Bull. B.O.C. 136(3), Table 1.
Agrees with: Wikipedia body lengths: White-naped swift 20.5–25 cm; White-collared swift 20–21.5 cm.
Description
Wikipedia, 'White-naped swift' (breeding section).
Shape
Drawn from the length and width, with the taper estimated from the typical eggs of its group (how these eggs are drawn).

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