Providing evidence to improve practice

Individual study: Comparison of the breeding success of collared flycatchers Ficedula albicollis nesting in nest boxes and natural cavities in Bialowieza National Park, Podlaskie, Poland

Published source details

Mitrus C. (2003) A comparison of the breeding ecology of collared flycatchers nesting in boxes and natural cavities. Journal of Field Ornithology, 74, 293-299

Background

This study investigated the breeding ecology of collared flycatchers Ficedula albicollis nesting in nest boxes and natural cavities in an area of old-growth oak Quercus –lime Tilia–hornbeam Carpinus forest within Bialowieza National Park (52°41'N, 23°52'E), Podlaskie, north-eastern Poland.

Action

 

In one section (25.5 ha) of the study site, 60 nest boxes were erected on trees at a height of 1.5 m and at least 25 m apart. Boxes had a basal area of 114 cm², with a 3.4 cm diameter entrance hole located 15 cm above the bottom of the box. Any old nests were removed from boxes before the start of each breeding season. In the second, contiguous, section (36 ha) of the study site, all breeding flycatchers nested in natural cavities.

During 1993–1999, active nests in boxes and natural sites were visited regularly to collect data on various reproductive parameters: first-egg laying date; clutch size; partial egg loss (the proportion of eggs that did not hatch in nests where at least one egg did); partial nestling loss (the proportion of nestlings that died before 14 days old in nests where at least on chick fledged); and the number of nestlings that fledged from successful nests (i.e. those from which at least one chick fledged). Breeding data from 1994 (when nest boxes were replaced) were excluded from analyses.

 

Consequences

 

Although they were found to vary from year-to-year, overall there was no significant difference in the first-egg date or clutch size (average: 6.1; range: 4–9) of clutches in nest boxes and natural cavities. Similarly, there were no significant differences between boxes and natural sites in rates of partial loss of eggs (23% versus 27%) or nestlings (35% versus 32%). As a result, the average number of nestlings fledged from successful nests was similar in boxes and natural sites (4.9; n = 122 and 150 nests). However, rates of (complete) loss of clutches or broods owing to predation were lower in boxes (0–28%) than in natural cavities (20–54%) in all six years analysed.

Note: If using or referring to this published study, please read and quote the original paper, the abstract of which can be viewed at: http://www.jstor.org/stable/info/4131032