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The Middle Spotted Woodpecker was cited in the Aragonese Pyrenees for the first time in 2019, and a couple nested in 2021. In spring 2022, and additionally in the following autumn and winter, a systematic surveys was carried out in forests with oaks in the Ribagorza region. Eleven territorial individuals were detected in forests dominated by the cerrioid oakQuercus cerrioidesdistributed in an upper section of the Ésera river valley. The origin of this population is unknown, but it could be related due to the existence of a relict population that would have gone unnoticed. It is more likely due to the arrival of individuals from some source population. The closest population is located approximately 30 km away on the northern slope of the Pyrenees, separated by a mountain barrier of more than 2,300 m, while the closest known one on the southern slope is located in the Navarrese Pyrenees, more than 100 km. The Middle Spotted Woodpecker is considered a sedentary species, with very limited dispersal movements. The establishment of this new and apparently isolated population could suggest that the species has a greater dispersal and colonizing capacity than has been attributed., El pico mediano fue citado en el Pirineo aragonés por primera vez en 2019, y se confirmó la reproducción de una pareja en 2021. En primavera de 2022, y adicionalmente en el otoño e invierno posteriores, se realizaron muestreos específicos en bosques con robles en la comarca de Ribagorza. Se detectaron 11 individuos territoriales en bosques dominados por el roble cerrioideQuercus cerrioides,repartidos en un tramo superior del valle del río Ésera. Se desconoce el origen de esta población, pero se podría relacionar por la existencia de una población relicta que hubiera pasado desapercibida, aunque parece más probable que se originara por la llegada de individuos de alguna población fuente. La más cercana se encuentra en la vertiente norte del Pirineo, a unos 30 km, separada por una barrera montañosa de más de 2.300 m, mientras que la más cercana conocida en la vertiente sur se sitúa en el Pirineo navarro, a más de 100 km. El pico mediano se caracteriza por ser una especie sedentaria, con movimientos dispersivos muy limitados. El establecimiento de esta nueva población, aparentemente aislada, podría sugerir que la especie podría tener una mayor capacidad dispersiva y colonizadora de la que se le atribuye.

Analysis of ecological time series allows to assess the relative contribution of density-dependent and density-independent factors influencing the regulation of the population of a species. In this study, we investigated whether the annual fluctuation in the population of Middle Spotted Woodpeckers Dendrocoptes medius can be attributed to the direct or delayed density-dependent regulation or to the density-independent factors such as weather conditions during the preceding winter and previous breeding season and/or disturbance in the habitat associated with sanitary felling and salvage logging of trees. This study was conducted in the Czeszewo Forest Reserve, which protects the remnants of semi-natural flood-plain forest, and in the Łówkowiec Forest, which is a managed oak-dominated stand, during 19 seasons (2001–2019). Time series diagnostic revealed that the growth rate of population of Middle Spotted Woodpecker in protected semi-natural riverine forest and in managed oak forest was determined by first-order negative feedback, suggesting an important role of direct density-dependent mortality in the regulation of an equilibrium in population size. The effect of density-dependent process varied between study sites, being lower in riverine forest, where population size has increased distinctly in recent years. In both study areas, we detected strong positive effects of wind chill temperature during the preceding winter on population growth rates. We did not find evidence for the assumption that the increase in population growth rate is affected by weather conditions in the previous breeding season and by the disturbance in the habitat associated with sanitary felling and salvage logging of trees. Our results suggest that Middle Spotted Woodpeckers can benefit from global climate warming by an enhanced rate of winter survival or an increase in the accessibility of food, e.g., insects and other arthropods. The lack of time-lag significant correlations between population fluctuations suggests local habitat conditions, e.g., forest management, can modify inter-annual variability in time series of the Middle Spotted Woodpecker.

[Abstract] Context Natal dispersal critically influences eco-evolutionary dynamics and the persistence of spatially structured populations. As both short- and long-distance movements contribute to population persistence in fragmented landscapes, understanding dispersal requires assessing phenotypic and environmental effects on a wide range of distances. Objectives To assess phenotypic and environmental correlates of dispersal movements in fragmented landscapes. Methods We radio-tracked juvenile middle spotted woodpeckers in fragmented landscapes to assess phenotypic and environmental effects on emigration age, transfer duration (in days), and transfer distances. Results Large fledglings and those in good condition emigrated earlier than smaller individuals and those in worse condition. Birds in better condition also reduced transfer duration. Overall, females dispersed earlier, remained shorter at transfer and moved further than males. However, while females increased transfer distances with increasing connectivity, males increased distances with decreasing connectivity. Emigration age increased with decreasing patch size and increasing patch quality, and with decreasing population density in patches with soft edges. Both transfer duration and distance increased with decreasing population density. Conclusions The correlations between phenotypic traits of fledglings and their posterior movements suggest that early-life conditions influenced dispersal through carry-over effects. Early emigration from low-quality and high-populated patches can be a behavioural mechanism to quickly escape adverse natal conditions, but population density effects were modulated by edge hardness. Finally, because reductions in connectivity led to similar transfer distances between sexes through a reduction in female distances, a lack of sex-biased dispersal can be a previously overlooked effect of habitat isolation that may alter eco-evolutionary dynamics. Open access funding provided by Swiss Ornithological Institute. Several grants and institutions covered our expenses: FPU grant of the Spanish Ministry of Education to CC; grants by Junta de Castilla y León, University of León, Xunta de Galicia (Ángeles Alvariño and Plan I2C grants), and Schifferli scholarship from the Swiss Ornithological Institute to HR. The Spanish Ministry of Education and Science (REN 2002-03587/GLO) and Xunta de Galicia (INCITE08PXIB103259PR, ED431C 2018/57) partly financed this research Xunta de Galicia; INCITE08PXIB103259PR Xunta de Galicia; ED431C 2018/57

In the spring of 2018, 18 nests of the Middle Spotted Woodpecker (Dendrocoptes medius) were surveyed in a 300 hectare area of the forest region in the south and north of Yasouj. Egg-laying began in late March. Clutch sizes were between three and seven (mean: 4.29 ± 1.25, median: 4, N = 8). The incubation period varied from 11 to 13 days (mean: 12.4 ± 0.89 days). The number of eggs that hatched in successful nests (N = 8) ranged from 2 to 5 (mean: 3.75 ± 0.89). Hatching percentage (N = 7) was 90%. Duration of the nestling period was 23–25 days (median: 24 days). Fledging dates ranged from Apr 28 to June 10, and most chicks (77%) fledged in the first ten days of May. Number of fledglings from successful nests (N = 17) ranged from 1 to 5 (mean: 3.58 ± 0.71), whereas the mean number of fledglings from all nests (N = 18) was 3.39 ± 1.09. The percentage of successful nests (at least one fledged young, N = 17) was 94.4%. The overall duration of breeding varied from 39 to 43 days (mean: 40.8 ± 1.48 days).

The distribution of the Middle Spotted Woodpecker (Leiopicus medius) is restricted to mature deciduous forests with large trees, mainly oaks (Quercus spp.). Intensive forest management resulted in the loss of many suitable habitats, thus resulting in a decline in the population of this species. This study aimed to identify the parameters of foraging sites in the breeding season (April to June) and in the non-breeding season (other months). The research was conducted in the primeval oak-lime-hornbeam forest of the Białowieża National Park, where foraging woodpeckers were observed and detailed parameters of foraging sites were recorded. During the breeding season woodpeckers foraged primarily on European hornbeams (Carpinus betulus L.), but in non-breeding season the use of this tree species decreased by a factor of two, whereas the use of Norway spruces (Picea abies L.) increased more than twice. The most preferred tree species as a foraging site in both seasons was pedunculate oak (Quercus robur L.). In the non-breeding season, woodpeckers foraged at sites located higher, and the foraging session was longer compared with the breeding season. In both seasons, woodpeckers preferred dead and large trees and prey gleaning from the tree surface was their dominant foraging technique. Our results confirmed the key role of oaks and large trees, but also revealed the importance of European hornbeams and Norway spruces as foraging sites for the Middle Spotted Woodpecker.

Population divergence could be strongly affected by species ecology and might not be a direct response to climate‐driven environmental change. We tested this in the middle spotted woodpecker (Dendrocoptes medius), a non‐migratory, low‐dispersal habitat specialist associated with old deciduous forests of the Western Palearctic. We present the first phylogeographic study of this species integrating genetic data (three mitochondrial loci, one autosomal and one Z‐linked intron) with species distribution modelling. Based on this species ecology, we predicted that the middle spotted woodpecker could have colonized its current range from multiple Last Glacial Maximum (LGM) refugia and that strongly structured populations could be expected. Indeed, we discovered a strong genetic divergence between Asian and European populations, with a split estimated at around one million of years ago. This was surprising given only slight intraspecific variation in plumage and morphology. Although there was no significant phylogeographic structure within the Asian and European groups, we cannot exclude the possibility of multiple refugia within either group during the LGM. This has to be further investigated with more extensive geographic sampling and larger number of variable independently evolving markers. Future studies should also investigate potential differences in vocalizations and ecology between the two groups. Lineages showing similar level of genetic differentiation including woodpeckers are often treated as species‐level taxa. Comparison of our results with the phylogeographic history of other woodpeckers, suggests that sympatric species with similar life‐histories might have idiosyncratic phylogeographic patterns probably resulting from different ecological requirements or historic stochasticity.

The disputed occurrence of drumming in Middle Spotted Woodpecker Dendrocoptes medius is due to a lack of sufficient, substantive evidence. In order to obtain a more reliable resource for assessing possible use of drumming in this species, breeding pairs were observed close to potential nest holes in south west France over five years. Drumming was heard in two of the six territories identified and sound recordings were made over four breeding seasons. Analysis of the recorded files consisted of counting and measuring intervals between strikes in all instrumental signals consisting of or containing drumrolls. The results showed that a form of drumming was performed but that it was infrequently produced in a discrete roll. It was usually soft and lacked the regularity of pattern found in the territorial drumrolls of other European woodpeckers. There was also a marked lack of consistency in the amplitude of strikes. As an acoustic signal, this study suggests its principal function to be a communication between partners in relation to the location and construction of a nest site.

Acoustic communication is an important part of behaviour in many bird taxa. In most woodpecker species drumming functions in mate attraction and territory defence. However, woodpeckers also produce calls, which function has been less studied to date. Unlike other woodpeckers, the Middle Spotted Woodpecker Dendrocoptes medius, which is the subject of our study, drums very rarely. Instead, it uses a number of calls, which functions have not been tested to date. We aimed our study at the identification of different calls and assessing their function, both by observation of spontaneous interactions between individuals and playback experiments. We distinguished three calls of different spectral characteristics and functions. Call-1 was mostly uttered by individuals sitting on the branch or a trunk. It was an initial response of territorial pairs to any disturbance within a territory. It signals general anxiety and/or arousal of territorial individuals. Call-2 was mostly uttered by the individuals during flight and it accompanied territorial conflicts and trials to remove the intruder from the territory. It warns the intruder about a territory owner’s readiness to a direct fight. Call-3, characteristic for floaters, was a persistent vocalisation without any obvious stimulus. Acoustic analyses of call-3 revealed that it was individually distinctive and the experimental approach confirmed that woodpeckers were able to distinguish between calling floaters. Thus, Call-3 functions as a vocal signature of unpaired individuals.

Citizen science (i.e. monitoring or research schemes with volunteer participation in data collection) is becoming an increasingly used tool that may yield reliable estimates of species distribution ranges. In 2017 and 2018, we assessed the fine-grain distribution and habitat use of the Middle Spotted Woodpecker in the Basque Country (N Spain) by combining two citizen science approaches: opportunistic observations gathered from internet collaborative databases, and standardised records collected by volunteers trained with a species-specific fieldwork protocol. Six out of the thirty-four opportunistic observations were located out of previously known distribution ranges. Because the reliability of those observations was difficult to assess, opportunistic observations should be validated to avoid false positives. As for the species-specific approach, Middle Spotted Woodpecker occurrence was examined by conducting itineraries with point counts and audio-stimulation, sampled twice during the pre-breeding season, in 95 UTM units of 1 km 2 . Woodpeckers were recorded in 29 of those units. In combination with recent species-specific studies, our results show that Middle Spotted Woodpeckers occurred mainly in a core, continuous range (69 positive units in and around the Izki forest) and in two smaller ranges (6 units in Montes de Vitoria and 5 units in Sierra de Entzia). Out of previously known distribution ranges, the species-specific approach showed that woodpecker occurrence was negatively affected by the distance to the core Izki forest and, to a lesser extent, positively influenced by the tree basal area of the forest stand. While the species-specific fieldwork approach allowed to improve the delineation of distribution ranges and the assessment of habitat use, the opportunistic approach pointed out to overlooked ranges but showed limited efficacy to assess the fine-grain distribution of the Middle Spotted Woodpecker.

Standing dead trees may be a limited resource for woodpeckers in managed forests, especially for species that rely on dead wood for their nest or roost cavity, and as foraging sites. Effective conservation strategies for woodpeckers require a detailed knowledge of species’ responses to dead wood availability. To investigate the importance of standing dead wood (snags) for the abundance and nest-site use of the great spotted woodpecker Dendrocopos major and middle spotted woodpecker Leiopicus medius in mature riverine forests, we compared the responses of birds between two periods—before mass mortality, and during a pulse in standing dead trees. The density of standing dead trees available for cavity excavation by the great spotted woodpecker and the middle spotted woodpecker increased significantly during the study period: 37-fold and 4-fold, respectively. Temporal trends in the abundance of both woodpecker species from 2000 to 2015 were not significant. Great spotted woodpeckers were significantly more likely to use dead trees and places with wounds in species other than oak and ash during the outbreak period than in the pre-outbreak period. Middle spotted woodpeckers were significantly less likely to excavate cavities in tree species other than oak and ash in the outbreak period, but dead trees were more likely selected. An interspecific comparison suggests that the probability of a nest-hole having been excavated by a middle spotted woodpecker increased with a nest-hole sited in ash, in a dead tree, in a limb/branch, and decreased with a nest-hole in a closed forest. These findings suggest that woodpecker species, especially weak excavators, may benefit from an increase in dead wood availability leading to nest niche shifts into more favorable substrates for cavity excavation. However, a strong increase in dead wood availability does not modify the general pattern of niche partitioning between great spotted and middle spotted woodpeckers. Conservation plans for the specialized middle spotted woodpecker must consider the preference for dead and decaying trees. The decreasing number of large ashes and oaks, and the lack of natural regeneration of the latter species, may negatively affect the middle spotted woodpecker in the future.

The Middle Spotted Woodpecker (Leiopicus medius) is a strict forest bird whose habitat preferences during the breeding season are well known. However, a lack of information about its habitat selection during the non-breeding season may hamper recommendations for the management and conservation of the species. Here we study habitat selection of this woodpecker at its southwestern boundary range (Izki Natural Park, northern Spain) during the non-breeding season (October–December) by means of a use–availability approach. We also examined seasonal differences in habitat use between the breeding season (April–May) and the non-breeding season. Results of ANOVA and backward-stepwise logistic regression revealed a clear selection of high forest cover, large Pyrenean oaks (Quercus pyrenaica), and presence of dead trees during the non-breeding season. Despite very similar habitat use in both seasons, minor but interesting differences between seasons were observed, with a potential expansion during the non-breeding season into less mature forests (lower forest cover and fewer large trees) with a greater abundance of dead trees. These differences may reflect seasonal changes in the spatial requirements of the species and a decrease in food abundance during autumn–winter. On the basis of these findings, we propose management measures to improve the conservation status of the species in the Iberian Peninsula.

Despite previous inventories and atlas of the avifauna in the Basque Country, Northern Spain, the dense population of the Middle-spotted Woodpecker Leiopicus medius in the Izki forest was not discovered until the 1990’s. This population mainly occupies a 3,700 ha Quercus pyrenaica forest, showing an average density of 0.89 territories/10 ha. The occurrence and abundance of territories is positively associated to the density of large caducifolious Quercus trees (>35 cm diameter). While nesting trees are apparently easily available, large trees for foraging could be a more limiting resource, given the historical exploitation regime of the forest. There are several other massifs in the region with smaller populations, but the functional connectivity, demographic and dispersal dynamics relating the core Izki and the peripheral areas have not been investigated. The conservation relevance of the Izki population in the Spanish context is high and given the need to understand the effects of forest management, future research should include spatial ecology, breeding performance as well as population monitoring.

Conservation biologists often use some specialized species as surrogates for communicating conservation needs, e.g. to signal states and changes in ecosystem. This requires a detailed knowledge of a species’ habitat demands and relationship between its occurrence and abundance, and certain environmental conditions. This paper explores the relationship between the occurrence and abundance of middle spotted woodpecker (Leiopicus medius) and structural, compositional, and functional elements of forest naturalness in three different forest landscapes in Poland, which encompass a wide spectrum of species’ habitats. Neither compositional nor functional elements of forest naturalness seemed to affect species’ distribution. In all studied areas, environmental variables related to the structural elements of forest naturalness, e.g. the share of old and uneven-aged stands, number of large living trees, positively influenced the occurrence and abundance of middle spotted woodpecker. Mature, unevenly structured forests might occur as a result of sustainable forest management, aimed at preserving the continuity of old stands and the maintenance of diverse age and species’ structure, providing suitable habitat condition for the species. Therefore, both presence and abundance of middle spotted woodpeckers can serve as indicators of wildlife-friendly forest management in deciduous forests.

The main goal of this study is to get a better insight of the habitat requirements for the Great- and Middle Spotted Woodpeckers. Woodpeckers are forest specialists, threatened all over Europe mainly by the loss of forest habitats and also by the loss in quality of the habitat by reducing the food sources and nesting sites. Both species showed a strong preference for oaks, lime, large trees and dead wood for nesting, but Middle Spotted Woodpecker proved to be more selective in terms of tree species. Nest-height was influenced by tree diameter. Both species have the same nesting preferences for Turkey oak, lime and Pedunculate oak, in a Quercetum farnetto-cerris type of forest. The orientation of the nest hole on the tree was mainly NE-E-SE for Middle Spotted Woodpecker and N-NE-E for Great Spotted Woodpecker.

Over the past centuries, many forests in Europe have undergone massive changes resulting in loss, fragmentation and degradation of habitats and a decline in biodiversity. Due to their habitat needs, woodpeckers are generally considered to be excellent indicators of forest habitat quality and biodiversity. In the EU and in Switzerland, the middle spotted woodpecker Dendrocopos medius acts as a flagship species for nature conservation in forests. After several decades of decline, the population of this indicator species more than doubled between 2002 and 2012 in the Canton of Zurich, northern Switzerland. The reasons for this positive trend are unknown. A new hypothesis states that the availability of ivy berries Hedera helix, sometimes eaten by the middle spotted woodpecker, has increased over the same time period and could have contributed to the population growth. Based on the population monitoring in the Canton of Zurich from 2012, the availability of trees with ivy at sites with and without presence of the middle spotted woodpecker was examined in eight forests. At the same time, differences in the availability of oaks Quercus sp. and standing dead trees were studied, two habitat factors well known to be important for the middle spotted woodpecker. As proxy for the availability of these three habitat factors, distances from playback points with and without woodpecker presence to the closest representatives of those resources were measured. Additionally, the distance to the closest living tree was recorded. Results revealed a significantly shorter average distance to the closest oak and, as a tendency, to the closest standing dead tree, respectively, at points with middle spotted woodpecker presence than at points without observations of the species. In contrast, neither the mean distance to the closest tree with ivy nor the mean distance to the closest living tree differed between playback points with and without response from the middle spotted woodpecker. Counting annual rings on cross-sections of 10 ivy stems revealed an average age of 23 years, suggesting that availability of ivy on trees might have increased over the last two decade. This study confirmed that large oaks and standing dead trees are important for the occurrence of the middle spotted woodpecker, whereas the availability of trees with fruiting ivy did not contribute significantly to explaining the presence or absence of the species.

This paper explores the influence of forest structural parameters on the abundance and distribution of potential habitats for the middle spotted woodpecker (Dendrocopos medius) in three different forest landscapes in Poland. We applied predictive habitat suitability models (MaxEnt) based on forest inventory data to identify key environmental variables that affect the occurrence of the species under varying habitat conditions and the spatial configuration of suitable habitats. All models had good discriminative ability as indicated by high AUC values (> 0.75). Our results show that the species exhibited a certain degree of flexibility in habitat use, utilizing other habitats than mature oak stands commonly associated with its occurrence. In areas where old oakdominated stands are rare, alder bogs and species-rich deciduous forests containing other rough-barked tree species are important habitats. Habitat suitability models show that, besides tree species and age, an uneven stand structure was a significant...

The diet of a breeding pair of Barbary Falcons (Falco pelegrinoides) was studied at Dena National Park, southwestern Iran, in the 2011-2013 breeding seasons by identifying species occurring in prey remains, an analysis of pellets and by video recording. The prey items belonged to 14 species of bird and two orders of insect. Birds composed the greatest proportion of the diet, comprising 95.3% by frequency and 99.9% by biomass. Bee-eater (Merops apiaster) was taken most frequently, but Wood Pigeon (Columba palumbus) and Middle Spotted Woodpecker (Dendrocopos medius) contributed more by biomass. Species that occurred in open habitats (e.g., Syrian Woodpeckers, Dendrocopos syriacus) or were of medium or large-size (e.g., Common Cuckoo, Cuculus canorus, Chukar and Common Magpie, Pica pica) were taken more than expected based on their availability. Altogether, the diet of the Barbary Falcon is based on the more abundant species, those of medium-size (50-120 g), and those frequenting open habitats.

We used three woodpecker species as umbrella species for old deciduous forests, and analysed their preferences in an area with old pollarded oaks in the Taurus Mountains, Turkey. Using plot inventories, we physically characterised trees utilised for nesting and foraging amongst woodpeckers in general and the Middle Spotted Woodpecker (Leiopicus medius) in particular. Trees more frequently visited by foraging woodpeckers differed from randomly chosen trees by being taller, having a larger circumference, greater bark furrow depth and shorter distance to neighbouring trees. Nesting trees were taller, had a higher proportion of dead wood but a lower surface area of natural cavities. Our results suggest that the woodpeckers in the study area rely upon woodlands containing mature trees, thus have the potential to function as suitable umbrella species’ to highlight the conservation value of oak forest habitats in southern Turkey. © 2016 Taylor & Francis.

Climate change has been widely recognized as a key factor driving changes in species distributions. In this study we use a metapopulation model, with a window of suitable climate moving polewards, to explore population shifts and survival of woodland birds under different climate change scenarios and landscape configurations. Extinction vulnerability and expansion ability are predicted for the middle spotted woodpecker Dendrocopus medius and two alternative r-K strategies under west European climate change scenarios of 1, 2 and 4°C temperature increase per century, corresponding to isotemperature velocities of ca 2, 4 and 8 km yr-1. The simulated northward expansion of the bird's distribution is typically in the range of only 0–3 km yr-1, in spite of 10–20 times larger maximum dispersal distances. This is too slow to track the climate change-driven range contraction of 4 or 8 km yr-1 in the south resulting in metapopulation extinction. Especially K-selected (large-bodied) species are vulnerable in the simulations. With a temperature increase of 4°C per century bird species go extinct within 104–178 yr. We present a simple approximation formula to predict the mean time to metapopulation extinction using 1) the rate of climate change, which determines the speed of range contraction in the south, 2) the size of the distribution range, which serves as a buffer against extinction, and 3) the northward expansion velocity, determined by species traits and landscape properties. Finally, our results indicate that the northward expansion rate is not constant. It will be initially lagged suggesting that recently observed expansion rates might be underestimations of future northward expansion rates

Results from the monitoring programs of the Swiss Ornithological Institute show that the breeding populations of several forest species for which deadwood is an important habitat element (black woodpecker, great spotted woodpecker, middle spotted woodpecker, lesser spotted woodpecker, green woodpecker, three-toed woodpecker as well as crested tit, willow tit and Eurasian tree creeper) have increased in the period 1990 to 2008, although not to the same extent in all species. At the same time the white-backed woodpecker extended its range in eastern Switzerland. The Swiss National Forest Inventory shows an increase in the amount of deadwood in forests for the same period. For all the mentioned species, with the exception of green and middle spotted woodpecker, the growing availability of deadwood is likely to be the most important factor explaining this population increase.

I investigated sexual differences in morphology and foraging behaviour in the nearly monomorphic Middle Spotted Woodpecker Dendrocopos medius. In the northeastern Swiss lowlands, radiotracked birds were observed from 1994 to 1996 between January and June. The sexes overlapped in all morphological characters, with males (n = 25) being on average larger than females (n = 17). Bill-length and length of the crimson-red crown patch were most useful to discriminate the sexes. Sex-specific differences in foraging behaviour were found both within and between the prebreeding and breeding periods concerning the use of tree species, foraging techniques, relative height zones and living and dead substrates within a tree. Overall, both sexes had broader niches in the prebreeding than in the breeding period and niche overlap was larger during the latter period. Hence, sex-specific differences were more pronounced in the prebreeding than in the breeding period, indicating different niche use of males and females in the two periods. These varying patterns of sex-specific differences imply that niche segregation results from behavioural plasticity, probably based on dominance relationships between the sexes, rather than from sexual dimorphism.

On behalf of the Federal Office for the Environment (FOEN), the Swiss College for Agriculture established the basis to foster oak species in Switzerland. For this, the growth areas of three oak species, common oak (Quercus robur), sessile oak (Q. petraea) and pubescent oak (Q. pubescens) were assessed throughout the entire country. The assessment was based on their physiological potential, their natural growth area and on the appearance of the middle spotted woodpecker. In addition, the older mixed oak stands were surveyed. These fundamental data were collected with a geographical information system and analyzed for each canton. Altogether, approximately one-fourth of the Swiss forest area is suitable for oak. The natural oak growth area covers however 38 500 ha only. About 19 000 ha of forest are populated by the middle spotted woodpecker and extended older mixed oak forests are found on approximately 24 500 ha. According to the applied evaluation matrix, the greatest potential for fostering oak species lies in eight cantons: Aargau, Zürich, Solothurn, Thurgau, Vaud, BaselLandschaft, Ticino and Schaffhausen.

In many parts of the world’s forests, intensive management has resulted in habitat loss for several species. Among these, specialised woodpeckers (Aves: Picidae) have been affected negatively due to their high requirements for resources that are scarce in managed forests. We used the gradient of anthropogenic impact on forests in northern Europe’s Baltic Sea region to (1) assess the relationship between the presence of four focal woodpecker species and forest naturalness and (2) quantify their requirements regarding specific resources in four different areas (south-central Sweden, southern Sweden, Lithuania and northeastern Poland). This study focused on specialised woodpecker species of the Dendropicini tribe: the three-toed (Picoides tridactylus), middle spotted (Dendrocopos medius), white-backed (Dendrocopos leucotos) and lesser spotted (Dendrocopos minor) woodpeckers. The occurrence of these species in landscape units of 100 ha was generally related positively to the degree of forest naturalness and to the amounts of resources considered critical for the suitability of their respective habitats. For the middle spotted woodpecker, basal areas P1.0 m 2 /ha of large-diameter deciduous trees (DBH P 40 cm) were associated with a high probability of occurrence (P0.9). For the white-backed woodpecker, the same probability of occurrence was found for basal areas P1.4 m 2 /ha of deciduous snags (DBH P 10 cm). Relationships between the occurrence of the three-toed and lesser spotted woodpeckers and snag abundance were more variable among study areas. The results suggest that specialised woodpeckers would benefit from an increase in the area of forest with natural properties. Moreover, they allow defining tentative quantitative targets for sustainable forest management.

The Nerussa-Desna woodland (south-western Russia) is one of the core areas for the Middle Spotted Woodpecker Dendrocopos medius, a habitat specialist restricted mainly to mature oak forests. Recent studies have shown a lower breeding density of the species in fragmented compared with continuous habitat. To evaluate reproduction as a possible mechanism underlying the fragmentation effects, we studied reproductive performance of the species in both continuous habitat and fragmented habitat in the forested landscapes of the Nerussa-Desna woodland. During 1997–2001, annual variation of reproductive indices in both continuous and fragmented habitat was insignificant. None of the indices was significantly lower in fragmented habitat though nestling losses were significantly higher in fragments. Timing of breeding in 2000 was later in fragmented than continuous habitat, probably due to differential landscape phenology. In fragments, fledging success in a year was inversely related to the mean amount of rain. On ...

Great- and Middle Spotted Woodpecker nest-hole dimensions and tree diameters at hole-entrance height were analyzed in order to test the hypothesis that Middle Spotted Woodpeckers, by making use of a thinner substrate and excavating smaller nest-holes, may reduce interspecific competition for nest-sites with Great Spotted Woodpeckers. It was found that only the vertical diameter of Great Spotted Woodpecker nest-hole openings and the entrance-hole area (49.2 mm, 17.8 cm2 respectively) were significantly larger than the corresponding parameters in Middle Spotted Woodpeckers (44.9 mm, 16.2 cm2). The average tree diameter at nest-height was 42.7 cm in Great Spotted Woodpeckers and 38.2 cm in Middle Spotted Woodpeckers, and did not differ between the two species. There were no correlations between the tree diameter at nest height and nest height in either species. The small variation in hole-entrance diameters (CV ≤ 10%) and the distance that a predator had to reach to plunder the nest (≥ 19 cm) are m...

From 1997–2003, forest management measures in favour of the vulnerable middle spotted woodpecker were conducted in an oak-hornbeam forest in northern Switzerland. In this study,we examine the consequences of these measures on population size and location of breeding cavities of middle spotted and great spotted woodpeckers. We found that population sizes of both species remained stable despite considerable forestry action taken in old oaks stands of vital importance for these woodpeckers. In areas where the two management measures «coppice-with-standards» and «thinning of coppicewith-standards stands» were applied, no differences in the number of breeding cavities of both species immediately before and after management intervention measures could be found. However, the proportion of breeding cavities of the great spotted woodpecker increased in old oak stands which were not subjected to management measures, while middle spotted woodpeckers used such stands as expected from their availability. We conclude that the two forest management measures are, at least on the short run, appropriate to the ecological requirements of the two woodpecker species.