Individual study: Artificial nest site relocation is moderately successful for burrowing owls
Smith B.W. & Belthoff J.R. (2001) Burrowing owls and development: short-distance nest burrow relocation to minimize construction impacts. Journal of Raptor Research, 35, 385-391
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Translocate nests to avoid disturbance
A small study from June-July in 1998 in one field impacted by agriculture in southern Idaho, USA (Smith & Belthoff 2001) found that burrowing owls Athene cunicularia exhibited mixed responses to nest relocation to a nearby natural buffer strip. Relocation distances averaged 153 m from old nests. Overall, two families (five fledglings) accepted the new nests (40%); two families (five fledglings) returned to the vicinity of the old nests one day after relocation (40%); and one family (five fledglings) disappeared from the field (20%). Dates of relocation events did not correlate with relocation outcomes. In 1999, one male and one female returned to the relocated sites and successfully fledged young (20% return rate). However, during 1999, none of the 15 fledglings from the 1998 nests was observed. The buffer strip was 25 m wide on the outskirts of a field zoned for development. All nests were artificial burrow systems.
Provide artificial nesting sites for owls
A randomised, replicated study in prairie, shrubland and farmland in southwest Idaho, USA, in 1997-8 (Smith & Belthoff 2001) found that western burrowing owls Athene cunicularia hypugaea preferentially used artificial burrows with large (1,750 cm3) nest chambers, compared to small or medium (707 cm3 or 900 cm3) chambers (31 large chambers selected vs. six medium and seven small, a total of 81 burrows of each type available). Burrows with small (10 cm diameter) tunnels were also preferred, compared to those with large (15 cm diameter) tunnels (30 burrows with small tunnels occupied vs. 14 with large burrows, 72 of each type available). However, there were no differences in reproductive output between nest types. Burrows were arranged in clusters containing all burrow types and designed to resemble natural nests. Chambers were lined with soil and natural burrows nearby were blocked with rocks to ensure owls used artificial burrows.