An efficient survey method for estimating populations of Marsh Tits Poecile palustris, a low-density woodland passerine

ABSTRACTCapsule: 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 eff...