Study

Does nest basket size affect breeding performance of long-eared owls and Eurasian kestrels?

  • Published source details Charter M., Izhaki I. & Leshem Y. (2010) Does nest basket size affect breeding performance of long-eared owls and Eurasian kestrels?. Journal of Raptor Research, 44, 314-317.

Actions

This study is summarised as evidence for the following.

Action Category

Provide artificial nesting sites for owls

Action Link
Bird Conservation

Provide artificial nesting sites for falcons

Action Link
Bird Conservation

Provide artificial nesting sites for songbirds

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

    A replicated study in eucalyptus stands in farmland in Lower Galilee, Israel (Charter et al. 2010), in 2008-9, found that long-eared owls Asio otus fledged more chicks from small nest baskets, compared to large ones (1.25 fledglings/breeding attempt for eight attempts in large baskets vs. 3.7 fledglings/attempt for seven in small baskets). Differences in clutch size and hatching success were non-significant (3.3 eggs/clutch and 60% hatching success for large nests vs. 5.0 eggs/clutch and 64% hatching success for small nests) and owls occupied nest types with equal frequency. Nest baskets were metal bowls filled with coconut fibre and were either 30 cm in diameter and 16 cm deep (small) or 40 cm in diameter and 20 cm deep (large). Thirty eight of each type of nest were erected in 2007, with the positions of large and small nests exchanged in 2008. The study also discusses nest box use by Eurasian kestrels Falco tinnunculus.

     

  2. Provide artificial nesting sites for falcons

    A replicated study in eucalyptus stands in farmland in Lower Galilee, Israel (Charter et al. 2010), in 2008-9, found that Eurasian kestrels Falco tinnunculus nested with equal frequency and equal success in nest baskets of two different sizes (13 of 76 nests used, average of 1.8 chicks fledged/clutch for six clutches in small baskets vs. 2.5 chicks/clutch for six in large baskets). Overall productivity in this study was lower than previously recorded in nest boxes in the same region (2.2 fledglings/breeding attempt vs. 3.2 fledglings/attempt in previous studies). Nest baskets were metal bowls filled with coconut fibre and were wither 30 cm in diameter and 16 cm deep (small) or 40 cm in diameter and 20 cm deep (large). The positions of large and small nests exchanged in 2008. The study also discusses nest box use by long-eared owls Asio otus.

     

  3. Provide artificial nesting sites for songbirds

    A replicated study in eucalyptus stands in farmland in Lower Galilee, Israel (Charter et al. 2010), in 2008-9, found both jackdaws Corvus monedula and house sparrows Passer domesticus nested more frequently in nest boxes with small (7.5 cm diameter) entrances, compared to nest boxes with large (15 x 30 cm) entrance holes (jackdaws: nested in approximately 25% of 49 small-entrance boxes vs. 2% of 51 large-entrance boxes; sparrows: nested in 10% of small-entrance boxes and no large-entrance boxes). This may have been due to competition with barn owls Tyto alba which were able to enter the large-entrance boxes only. Boxes were attached to shaded parts of eucalyptus trees and the positions of large and small boxes were exchanged between years. This study also investigated nest box use by kestrels and owls.

     

Output references
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