Volume 47 • Number 2 • 2006
69 Assessment of the Middle Spotted Woodpecker Dendrocopos medius numbers in the "Dąbrowy Krotoszyńskie" bird refuge.
Ziemowit Kosiński Robert Hybsz
Abstract: The aim of the study was to assess the Middle Spotted Woodpecker numbers in the oak woods of the Jasne Pole forest district near Krotoszyn (51°41'N, 17°26'E), southern Wielkopolska. The woods are situated within an Important Bird Areas of EU, named "Dąbrowy Krotoszyńskie" (PL093). The research was conducted with the use of the survey sampling method on nine randomly selected sample plots covering jointly 1175 ha. In March and April 2005, three counts with vocal stimulation were performed on each plot. Within the study plots, 65 territories of the Middle Spotted Woodpecker were discovered, and its total population was estimated at 236 territories. Comparing the data from two neighbouring sample plots (Smoszew - 26-29 pairs, Stare Budy - 44-58 pairs), it can be presumed that at least 310-320 Middle Spotted Woodpecker pairs occur within the refuge. This indicates that the "Dąbrowy Krotoszyńskie" oak forest is one of the three most important refuges of this species in western Poland . Its abundance in the study plots was found significantly related with the coverage of deciduous forest (r=0.86, P=0.003), including oak woods older than 80 years (r=0.83, P=0.006). Within a few dozen years most of the oak tree stands will have reached the felling age, which will result in diminution of the oak forest area - and this seems the main factor threatening the Middle Spotted Woodpecker population within the "Dąbrowy Krotoszyńskie" refuge.
80 Abundance, location of breeding sites and habitat preferences of the Barn Owl Tyto
alba in the southern Podlasie region.
Abstract: The study was conducted in 2002-2005 in the southern section of the Podlasie region (administrative districts of Biała Podlaska and Łosice). In an area of 1758.5 km 2 , 22 breeding sites of the Barn Owl were discovered. The majority (77%) of the sites were situated beyond sacral buildings. Almost exclusively, the birds nested in stone buildings within densely built-up rural area (91% of the sites). Most commonly, the breeding sites were located in attics (50%) and ventilation openings in blocks of flats (32%). The habitat types which covered the greatest area of the Barn Owl territories were farmland (53% on average) and green crops (19% on average). Forty one per cent of the territories were characterized by a significant share of green land (>20% ), and arable land constituted over a half of the hunting territory in as much as 86% of the sites. The Jacobs preference index indicates that the Barn Owl avoids wooded areas (-0.50) and orchards (-0.33), preferring meadows (+0.22) and farmland (+0.19). Both green and arable land had a relatively stable share in the species territories, whereas the percentages of built-up area and forest varied. In nearly half of all controlled buildings (47.5%, N=75) occurrence of the Stone Marten Mustela foina was established, and these sites were not occupied by Barn Owls. In 6 cases (27%) the Barn Owl sites were located within the Tawny Owl Strix aluco territories.
89 Variation of the diet of the urban Kestrel Falco tinnunculus outside breeding season:
differences between territories.
Michał Żmichorski, Łukasz Rejt
Abstract: Between 1995 and 2003 the authors investigated the variability of the urban Kestrels diet during autumn (Oct.-Nov.), winter (Dec.-Feb.) and early spring (March). At 15 sites, 1752 pellets containing 2390 prey items were collected. The main part of the material came from four localities, which differed in proportion of dense and dispersed built-up areas, open and afforested territories. The food composition at these locations differed significantly depending on the season. The proportion of microtines in the diet was decreasing whereas that of birds growing with increasing habitat heterogeneity and afforestation of the areas around the localities. The mice proportion was inversely related with the dense and positively related with the dispersed built-up areas proportion. The breadth of the food niche of Kestrels was positively correlated with habitat heterogeneity and afforestation of the areas. Outside breeding season, the Kestrels in Warsaw can be characterized as food generalists. The foraging pattern observed among Warsaw Kestrels, especially diet shifting between different localities, indicates that in the case of urban populations holding the nest sites all year round is important, even if the birds are forced to change their diet composition.
Report No 22
97 Rare birds recorded in Poland in 2005.
Summary: This report includes 374 accepted records from 2005, as well as 31 earlier ones, concerning 93 species and subspecies. Two new species have been recorded for the first time in Poland , namely the Least Sandpiper Calidris minutilla and the Rufous-tailed Robin Luscinia sibilans (the second one for the Western Palearctic). Another species potentially new to Poland, the Bufflehead Bucephala albeola has been placed in category D. Highlights of the year were five second records of: the Ring-necked Duck Aythya collaris, Black-winged Kite Elanus caeruleus, Lesser Sand Plover Charadrius mongolus, Spotted Sandpiper Actitis macularius and Sardinian Warbler Sylvia melanocephala; the third of the Paddyfield Warbler Acrocephalus agricola; the third and fourth of the Ruddy Duck Oxyura jamaicensis; the fifth of the Red-rumped Swallow Cecropis daurica.
However, more has been altered in the list of the national avifauna due to further changes in taxonomy, concerning chiefly species splitting; moreover one species - the Cetti's Warbler Cettia cetti - has been removed as a consequence of an extraordinary revision, while two others - the Egyptian Goose Alopochen aegyptiaca and Ruddy Duck Oxyura jamaicensis - are now placed in category C, and so they are present in the checklist. Currently the national list contains 445 species.
Records of each species are first presented regionally in alphabetic order of the provinces, afterwards chronologically; they contain: date, number of individuals, sex and age (if known), documentation if present (photo, phono, video, specimen, etc.), location, district, and in brackets names up to three observers, further brief comments and references in some cases. The number codes following the species name mean: the first one - number of records slash number of individuals till 2004 inclusive, the second one - number of records slash number of individuals in 2005; "ca" means approximate number of records or individuals, "n" instead of a number - unknown number of those. The report includes an appendix (Aneks) containing not accepted records, and a list of revisions, i.e. reconsidered records, then complements of two former records.
125 Use of anthropogenic sources of mineral substances by Crossbills Loxia curvirostra.
Małgorzata Bylicka, Michał Ciach, Damian Nowak
Summary: In 2000-2005, in the Polish Carpathians Crossbills collecting mineral substances at sites of anthropogenic character were observed. The birds foraged at communication routes, steel constructions, fire-sites, walls of buildings and on the soil, feeding on sand, salt, rust, ash, mortar, brick and earth. Presumably, this is a common phenomenon directly related with the composition of the Crossbill diet (seeds). The substances mentioned can be sources of gastrolites or mineral compounds, protect the alimentary system or reduce the effects of toxins from the food. It cannot be excluded that this type of foraging plays also a social role - formation of flocks through family groups coming together. Foraging for mineral substances from anthropogenic sources is the most frequently recorded in the wintertime, which may be due to two co-occurring factors. A poor winter diet results in deficiencies of mineral substances, and harsh atmospheric conditions limit the access to mineral sources. This makes the birds look for alternative sites, devoid of snow, which are easier to find in man's neighbourhood. However, it is likely that the heavily digestible food of Crossbills forces them to collect some of the substances mentioned also in summer. Probably, then the birds use sources that are accessible in their environment.
130 Numbers of the Nightjar Caprimulgus europaeus in a fire-burnt area near Kuźnia Raciborska. Krzysztof Henel, Robert Kruszyk
Summary: In August 1992 a conflagration consumed 9060 ha of forest, mainly pine wood, north of Kuźnia Raciborska (southern Poland ). The consequence was appearance of favourable environmental conditions for the Nightjar. The study plot covered a part of the burnt area situated within the Rudy Raciborskie Forest Division, occupying 4500 ha. In 2003 a single control was performed - in the 2nd and 3rd decade of June, during which 80-85 displaying males (density 17.8-18.9 pairs/10 km 2 ) were observed within the study area. During the two 2004 controls (in the 2nd and 3rd decade of June, and the 1st of July) the species abundance was estimated at 80-90 breeding pairs (density 17.8-20.0 pairs/10 km 2 ) and 160-180 pairs on the whole fire-burnt area. The Nightjar territories were distributed evenly about the whole study plot. The birds occupied sites inside dense young pine woods, predominating in the fire-burnt area. The species density within the fire-burnt area in the Rudy Raciborskie Forest Division ranks among the highest in Poland . This results from the size of open space area and occurrence of deciduous tree species (birch, oak) both in the remnants of old tree stand and in the new stands, which is probably conducive to abundance of insects the Nightjar feeds on.
134 Decline of the Crested Lark Galerida cristata breeding population in Kielce in 1986-2005.
Summary: Data for 1986-2005 indicate that the Crested Lark breeding population of Kielce (area of 35 km2) has almost completely disappeared. In the study period, the species occurred jointly at 11 breeding sites within densely built-up area of the town. The year 1994 was characterized by the highest number of pairs (6-7) and individuals (16-19). At the site of its greatest and more permanent abundance (an area of 45 ha within the housing estates Świętokrzyskie and Na Stoku), in 1993-2005 the Crested Lark reached a density of 1.3 p/10 ha. In 1999-2000 and 2003-2005 there was probably only a single pair nesting in the town, but it was not observed in 2002. Kielce is a town situated amongst forests and surrounded by the ridges of the Góry Świętokrzyskie Mts, with scarce open areas of hilly landscape. Such environmental conditions are not conducive to more abundant occurrence of Crested Larks. It also seems probable that the disappearance of the species urban breeding grounds from Kielce is consequent on the changes of the town which involve reduction of open urban and suburban areas ruderal in character.
138 Predation of the Red Fox Vulpes vulpes digging for the Sand Martin Riparia riparia nests.
Summary: On 6th and 24th June, 2005, in one of three controlled Sand Martin colonies, situated within opencast sand working Biała Góra near Tomaszów Mazowiecki (Łódź Voivodeship), breeding chambers of the bird dug up by a Red Fox were discovered in the dome of a high escarpment. Twenty seven damaged nests were recorded, which constituted 6.4% of the number of all cavities. The mean depth of a ruined breeding chamber was 38.5 cm, its average distance from the scarp edge - 37.8 cm. Taking into account the 60-70% occupancy of burrows, which is typical of large colonies of the Sand Martin, and assuming that only occupied burrows were dug by foxes, it can be presumed that 9-10% of the broods got destroyed. Predators digging for Sand Martin nests from the surface of scarp is exceptional. This phenomenon had never been observed in foxes before.
140 Grass Snakes Natrix natrix in the Kestrel Falco tinnunculus diet.
Summary: During constant observations of the breeding sites of a pair of Kestrels, conducted in the central part of Szczecin in the 1st decade of May 2003-2005, the male was twice observed to have brought to the nest environs a Grass Snake, each ca 50 cm long. The snakes were killed and torn to pieces by the female. Besides, remnants of Grass Snakes were twice discovered in pellets, and three times Kestrels were recorded to bring into the nest a male Sand Lizard Lacerta agilis. In total, reptiles constituted nearly 7% of the biomass of food. Snakes had not been listed among the items of the Kestrel diet before.
143 Mystery bird 43: Sedge Warbler Acrocephalus schoenobaenus.
145 International Conference "Network for Bittern", 7.-9.12.2005, Sandy , UK.
Marcin Polak, Jarosław Krogulec