Nest-box versus natural-cavity nests of the eastern screech-owl: an exploratory study

  • Published source details Gehlbach F.R. (1994) Nest-box versus natural-cavity nests of the eastern screech-owl: an exploratory study. Journal of Raptor Research, 28, 154-157.


This study is summarised as evidence for the following.

Action Category

Provide artificial nesting sites for owls

Action Link
Bird Conservation
  1. Provide artificial nesting sites for owls

    A replicated, controlled study in 1967-75 in urban woodland in central Texas, USA (Gehlbach 1994), found that eastern screech owls Megascops asio (formely Otus asio) had equal nesting success in nest boxes as in natural nests (average of 3.9 eggs/clutch and 51% of eggs producing fledglings in nine nest boxes vs. 3.8 eggs/clutch and 57% of eggs producing fledglings in nine natural nests). The wood used in nest boxes (plywood, pine or cedar) and nest box size did not appear to affect use or reproductive success. Nest boxes had basal areas of 225, 400 or 625 cm2, with a 6.8 cm entrance hole 25 cm above the base. Boxes were erected 3-4 m above ground on large trees.


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