Ornis Polonica 2011, 52: 161–168
Woodpeckers abundance in the Białowieża Forest – a comparison between deciduous, strictly protected and managed stands
Wiesław Walankiewicz, Dorota Czeszczewik, Tomasz Tumiel, Tomasz Stański
Abstract: In 2007–2009 we counted all woodpeckers along seven transects (4.6–8.0 km long) in deciduous stands of the Białowieża Forest, NE Poland. Three transects ran along stands of the strictly protected part of the Białowieża National Park (BNP) and four in managed stands of the forest. The total number of recorded woodpeckers per 1 km of transect (hereafter treated as an index of abundance) was on average 9.0 (SE=0.4) in BNP and 5.4 (SE=0.4) in managed stands. The most common species was Great Spotted Woodpecker Dendrocopos major, while the least numerous were Wryneck Jynx torquilla, Grey-headed Woodpecker Picus canus in all transects, and Three-toed Woodpecker Picoides tridactylus in managed stands. In comparison with 1999–2001, indices of abundance of all woodpeckers increased in 2007–2009 by 1.4/km in BNP and by 0.8/km in managed stands due to increasing index of D. major. We found that woodpeckers’ situation in managed stands is getting worse compared to BNP. This study confirms the importance of ecological reference of the Białowieża National Park, especially for White-backed Woodpecker D. leucotos and Three-toed Woodpecker.
Ornis Polonica 2011, 52: 169–180
Numbers and dynamics of spring migration of geese in the Biebrza Basin
Michał Polakowski, Monika Broniszewska, Łukasz Jankowiak, Łukasz Ławicki, Marcin Siuchno
Abstract: In the years 2007–2010, the dynamics of spring migration of geese and the importance of the Biebrza Basin (NE Poland) was determined. 18 foraging areas were found, where 1,200–40,000 individuals were recorded, depending on the area. Areas grouping the biggest concentrations were located in Wizna, Middle and Lower subbasins. The dominant species was the Greater White-fronted Goose Anser albifrons (mean about 90% of all geese), whose spring migration lasted for the shortest period, peaking in the second or third decade of March. The biggest concentration of this species accounted for ca 38,000 individuals. Bean Goose A. fabalis made up mean 9% of all geese and the largest flock was ca 2,850 individuals. The peak of spring migration in the second decade of March. Greylag Goose A. anser migration peaked in the first decade of March. Barnacle Goose Branta leucopsis and Pink-footed Goose A. brachyrhynchus were regularly recorded. A large increase in the number of geese during spring migration was noted over the last 35 years in the Biebrza Basin. In 2007–2010, during the migration peak, the maximal number of geese on their feeding grounds was estimated on ca 100,000–150,000 individuals. The Biebrza Basin is the most important region for Greater White-fronted Goose in Poland, bringing together ca 70% of the population migrating through Poland and 10% of the population wintering in Europe.
Ornis Polonica 2011, 52: 181–195
Numbers and distribution of Lapwing Vanellus vanellus and Golden Plover Pluvialis apricaria in Poland in autumn 2008
Włodzimierz Meissner, Arkadiusz Sikora, Jacek Antczak, Sebastian Guentzel
Abstract: Following the first survey in 2003, in autumn 2008, Lapwings and Golden Plovers were counted in Poland. In October (282 sites surveyed), nearly 120 thousands of Lapwings and 52.6 thousands of Golden Plovers were counted, while respective numbers in November (151 sites surveyed) were 28.8 and 22.8 thousands. Both species were most numerous in northern Poland, where 64% and 79% of Lapwings and 81% and 92% of Golden Plovers were found. Lapwings most often were observed in flocks of 101–500 birds in both months, but the median flock size decreased from 400 in October to 112 in November. Flock size of Golden Plovers decreased from 215 (median) in October to 82.5 in November, and more smaller flocks were seen during the latter count. Flocks consisting of two species made up 24% of all in October and 65% in November; in most of them Lapwing was more numerous than Golden Plover. Lapwings were most often recorded on plowed lands, winter corns and bottoms of various water bodies, while Golden Plovers were found predominantly on winter corns. During October count, 5–11% of north European Golden Plover population and 2% of European Lapwing population were recorded in Poland, what indicates that Poland provides important stopover sites for both species.
Ornis Polonica 2011, 52: 196–210
Numbers and distribution of Bewick’s Swan Cygnus columbianus bewickii
in Poland in spring 2010
Łukasz Ławicki, Przemysław Wylegała, Maria Wieloch, Arkadiusz Sikora, Grzegorz Grygoruk, Andrzej Dombrowski, Sławomir Chmielewski, Wiesław Lenkiewicz, Radosław Włodarczyk
Abstract: A national census of Bewick’s Swans took place in Poland in spring 2010 with three counts conducted (13–21 March, 27 March–4 April and 10–18 April), which in total covered 338 sites. During subsequent counts 1,122, 1,214 and 253 swans were recorded on 74, 44 and 18 sites, respectively. Most of Bewick’s Swans were observed in lowlands (71–92% of all birds), with the Wielkopolska region holding biggest numbers. In northern Poland, 8–28% of Bewick’s Swans were recorded, while in highlands the species was rare. Flocks up to 10 individuals were the most frequent; the biggest flocks (119–230 inds.) were found at fish ponds in Wielkopolska region. During the first count, swans frequented predominantly river valleys and fields, during the second count – fish ponds and river valleys while during the last count they were mostly found at fish ponds. Young swans accounted for 8–10% of all birds. Among family flocks (N=41), these with 1 or 2 young predominated (82%). In spring 2010, at least 5% of Bewick’s Swan population wintering in NW Europe was recorded in Poland. This is about twice less than in some other years, when during migration peak numbers of Bewick’s Swans have been estimated for at least 2,000 birds.
Ornis Polonica 2011, 52: 211–218
Mate choice strategies and inbreeding avoidance in birds
Abstract: It is well established that progeny of inbred matings are less fit, and that inbred individuals suffer from reduced viability and fertility. Since inbreeding depression is costly, we may expect that individuals should avoid mating with close relatives or genetically similar members of the opposite sex. At the other hand, inbreeding avoidance may lead to considerable loss of breeding opportunities. This may stem, for example, from constraints on mate availability. If mate availability is low, we could expect that individuals may accept mating with close relative. In such situation individuals may try to avoid inbreeding indirectly for example by seeking for extra pair copulation. In this article, I review the empirical evidence for inbreeding avoidance via kin discrimination and mate choice among birds.
Ornis Polonica 2011, 52: 219–224
The use of aerial photographs to detect breeding sites of the Mute Swan Cygnus olor in Gdańsk
Abstract: This paper presents a new to Poland method of estimation of Mute Swan population basing on the analysis of aerial photographs. Here we present the data from the city of Gdańsk gathered in 2008 and 2010. Aerial digital photographs were taken on 9 and 10 May 2008 at the height of 1000 m. The photos were ortorectified with a pixel-size of 10 cm. All sites where adults were present on nests or nearby were assumed to be breeding localities. The breeding population of Gdańsk was estimated at 30–40 pairs, suggesting it’s the largest urban population of the species in Poland. It is likely that this method could be useful also for the detection of breeding sites and estimation of population sizes of other breeding bird species of large size. A variation of this method can be the use of photographs taken by mini drone helicopters flying at the level of a few to a few hundred meters.
Ornis Polonica 2011, 52: 225–228
Avifaunistic Commission Communiqué No 15. Cases of breaking verification rules
This announcement informs about cases of observations of rare species which require verification by the Commission, and are still being published without relevant acceptance. It is recommended that these cases are not treated as scientific facts.
Ornis Polonica 2011, 52: 229–230
Mystery bird 64: Tree Sparrow Passer montanus