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Characteristics of Great Spotted Woodpecker roosting holes are compared with those used for breeding. Neither postbreeding nor winter roosting holes differed from woodpecker nests with respect to tree species, condition, girth at breast height, cavity height or cavity direction. However, behavioural observations suggested that particular holes might be selected, probably in connection with microclimate condition and predator avoidance.
Analysis of 531 nest cards (Polish Nest Record Scheme) of the Great Spotted Woodpecker, obtained in the years 1970–2003 is presented here. The data is derived from almost the whole of Poland, except for the Białowieża National Park. From the material processed for the purpose of this study, the Great Spotted Woodpeckers appear to nest in various types of wooded habitats, especially in forests and they are very flexible in their choice of nesting sites, both in terms of age of tree stands and intensity of human penetration. As a rule, woodpeckers breed mostly in holes made in deciduous trees (oak, birch, and alder). More than 95% of nests were excavated in tree trunks, primarily in dead or weakened trees. Woodpeckers excavated their nest in the range of 0.5–19 m above the ground, with more than 75% of them found in the narrower range from 1–7 m. The height of cavity above the ground did not depend on tree species or vegetation type and was also weakly correlated with the height of tree stands. The openings of cavities showed no statistically significant differences in their geographical orientation. Although the information about woodpecker nests, gathered in the Nest Record Scheme does contain certain errors (such as “habitat preferences” of observers), the obtained results provided a better insight into the nesting ecology of this species in Poland.
Great Spotted Woodpecker is the most abundant and widespread European woodpecker species, and it thus contributes the most to the number of excavated tree holes – an important habitat resource for secondary hole users. However, majority of nest site characteristics data comes from boreal and temperate forests, with lack of information from Southern Europe. In this article, nest sites of the Great Spotted Woodpecker have been investigated in the continental forests of Croatia – a previously understudied area of this species’ range. A total of 41 active nest-holes found in the breeding seasons 2003 and 2004 are described. Nest-holes were mainly positioned below the crowns, in injuries of branch abscission. Nesting tree species were not used randomly: wild cherry Prunus avium in hill and pedunculate oak Quercus robur in riverine forests were preferred while hornbeam Carpinus betulus and maples Acer sp. were avoided. While tree species used for nesting vary across the Great Spotted Woodpecker range, and thus cannot be used as a uniform nest site predictor, defected wood spots on a tree, like scars of branch abscission, are identified as an important nest site clue and a habitat feature that is spatially more consistent. Nest-holes’ dimensions acquired in this research could not be clearly differentiated from those given for the other parts of the continent.
This study was carried out in Rome city from 1991 to 1999. In a total of 47 urban parks and suburban woods, 22 wooded areas were occupied by Great Spotted Woodpeckers during the breeding period. All woods greater than 50 ha in area were occupied by woodpeckers. On a five year scale, territorial stability was positively correlated with woodland size. The requirement of wooded area per territory was slightly higher in urban parks (6.7 ± 2.7 ha, n = 10 wooded areas) than in suburban woods (5.7 ± 1.3 ha, n = 5), and was negatively correlated to the vegetation cover. The area of woodland per territory in Rome was higher than in neighbouring deciduous oak woods. This suggests that urban habitats are of inferior quality for breeding Great Spotted Woodpeckers, probably owing to features of their vegetation and their isolation from other woodland patches. Maintaining mature stands of natural vegetation with old and dead trees in larger urban parks could be useful to encourage the occurrence of Great Spotted Woodpecker in cities.
Nest sites of nine common hole-nesting bird species were studied in the West Khentey Mountains, NE Mongolia. Among three excavators, the Great Spotfed Woodpecker used more aspens, larger trees, and more living or intact dead trees than the Lesser Spotted Woodpecker or the Willow Tit. Among non-excavators, the Nuthatch used mainly old holes of the Great Spotted Woodpecker, and the Red-throated Flycatcher frequently used those of the Willow Tit. Thus, the nest site characters of these two species resembled those of the original excavators, and their nests were placed higher than those of other non-excavators. The Coal Tit and the Great Tit used mostly branch holes in living trees. With respect to nest site use, the Daurian Redstart behaved as a generalist while the Common Treecreeper specialized in long slits. The nest site selection of excavators might be governed by body size, territory size and their different abilities of excavation. The non-excavators were best differentiated by their preferred hole type, and their tree use and nest site characters were mainly a consequence of the location of such holes. Interspecific competition did not appear to be important in the nest site use of hole-nesting birds in the study area.
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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