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Intensity of plumage colour may advertise individual condition, health and parasite resistance of birds. Although numerous studies confirmed such function of ornaments in songbirds, still very little is known about signalling properties of colour feathers in woodpeckers. We test whether the size and colour of a red cap displayed by both male and female Middle Spotted Woodpeckers are related to mass and length of tarsus, wing, tail and beak. We found that body mass was correlated with cap width and brightness in woodpeckers of both sexes. At the same time body mass affected reproductive success of individuals. This suggests that both cap width and brightness has the potential to signal individual condition in the studied species.
The aim of the study was to test whether the methods using the playback technique produce accurate data of population size when compared to the standard mapping and nest-searching methods. The three-visit method with audio-stimulation was found to produce data of the same accuracy (100%, n = 11 territories) as the standard mapping method, but the nest-searching method ahd single-visit with audio-stimulation yielded slightly lower estimates, 91% and 82% respectively, in comparison to the previously mentioned methods. However, the three-visit method with audio-stimulation was 2.2 times less time consuming than the five visits which used the standard mapping method (9h vs 20h). The three-visit method with audio stimulation could be appropriate for assessing distribution and abundance, and also for monitoring purposes.
Abundance, distribution and nest-site characteristics of woodpecker species (family Picidae), i.e., Great Spotted Woodpecker (Dendrocopos major L.), Middle Spotted Woodpecker (D. medius L.), Lesser Spotted Woodpecker (D. minor L.), Black Woodpecker (Dryocopus martius L.), Grey-faced Woodpecker (Picus canus Gmel.) and Wryneck (Jynx torquilla L.), coexisting in managed forest are described. All species preferred old deciduous forest stands (≥81 years old) as nest-sites, however, they differed in most aspects of nest site selection. Great- and Middle Spotted Woodpeckers excavated nest-holes most commonly in oaks (78 and 86% of nests, respectively), but Black- and Grey-faced Woodpeckers in beeches (71 and 100% of nests). However, placement of nest-holes within the same tree species differed among woodpecker species. Great Spotted- and Grey-faced Woodpeckers nested three meters lower (9 m) compared to Middle Spotted and Black Woodpeckers (12 m). Lesser Spotted- Woodpeckers excavated breeding holes relatively the highest in respect to tree height. With the exception of Lesser Spotted Woodpeckers, all specie used live trees as nest sites. Weaker excavators such as Middle Spotted- and Lesser Spotted Woodpeckers, nested more frequently in limbs and branches (31 and 25% of nests, respectively) compared to strong excavators, i.e., Great Spotted-, Black- and Greyfaced Woodpeckers (<8% of nests in limbs or branches). Weaker excavators more frequently selected dead tree fragments compared to strong excavators.
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