An efficient survey method for estimating populations of marsh tits Poecile palustris, a low-density woodland passerine
Author(s): Broughton, R.K., Dadam, D., Maziarz, M., Bellamy, P.E. & Hinsley, S.A.
Published: September 2018 Pages: 7pp
Journal: Bird Study Volume: 65 ( part 3 )
Digital Identifier No. (DOI): 10.1080/00063657.2018.1517243
Capsule: A playback survey comprising two visits to woodland in early spring can reliably detect Marsh Tits Poecile palustris and permit reasonable estimation of the number of territories.
Aims: To assess the efficacy of an efficient survey method for detecting and estimating populations of Marsh Tits.
Methods: Detection probability of colour-marked Marsh Tits, surveyed using playback, was assessed with Cormack–Jolly–Seber models. Reliability of territory estimates was compared between colour-marked and largely or wholly unmarked populations.
Results: Playback surveys over two visits in early spring were highly effective in detecting individual Marsh Tits. Territory estimates were similar for woods in years where less than 20% of the population was marked compared to years when a higher proportion of birds were colour-marked, although territories may be underestimated in larger woods with unmarked populations.
Conclusion: A playback survey comprising two visits in early spring is recommended as an efficient method of surveying Marsh Tit populations and locating individuals. A survey protocol is suggested.
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