Synchrony in the phenology of a culturally iconic spring flower.

We examine the flowering phenology of the cultural iconic Spring Snowflake Leucojum vernum, a considerable tourist attraction, recorded from two sites in western Poland. Flowering dates at the two sites were closely correlated but about 6 days later at the more natural area. The end of flowering was associated with the start of canopy leafing. Early flowering was related to a longer flowering season which may benefit ecotourism under future climate warming.

Profile of Selected Mineral Elements in Tibiotarsal Bone of the White-Tailed Sea Eagle in Its Natural Habitat.

Mineral bone composition (dry matter, bones ash, P, Ca, Zn, Mn, Mg, and Cu) and Pb levels of tibiotarsi of seven White-Tailed Sea Eagles were assessed. Lead intoxication in different bird species including waterfowl and raptors is being studied worldwide. The bones were analyzed for Pb by mass spectrometry with excitation in inductively coupled plasma (ICP-MS Elan DRC II) and for bone composition by Atomic Emission Spectrometer (Agilent 4100 Microwave Plasma). Pb levels ranging from 3.54 µg/g to 74.6 µg/g DM suggest that some of the investigated birds might have been intoxicated by Pb. Results of this analysis were divided into two groups of bones, with bone Pb levels higher and lower than Pb toxicity levels, and mineral bone compositions of both groups were compared. The present study shows the differentiation of bone mineral composition among seven examined White-Tailed Sea Eagles, considered a specific species in raptors. Pb intoxication may not have a major influence on mineral bone composition in raptors. It also suggests that assessing bone composition of raptor bones may help finding the possible cause of their deaths.

Energy crops affecting farmland birds in Central Europe: insights from a miscanthus-dominated landscape.

The expansion of energy crops such as miscanthus Miscanthus x giganteus has changed the habitat of European farmland birds. However, most studies on the subject are based in Western Europe. We surveyed the avian community in a sample bioenergy landscape in Poland to investigate the pattern of use of the crop by birds in Central Europe. During a year-long survey, 80 species were noted, with 32 sighted in miscanthus. The number of bird sightings was negatively correlated with the area covered by miscanthus in study plots. In contrast to results from Western Europe, most woodland-generalist bird species tended to avoid miscanthus. Farmland species (e.g. the corn bunting Miliaria calandra; the tree sparrow Passer montanus; the starling Sturnus vulgaris; the yellowhammer Emberiza citrinella) were less frequently sighted in the crop than in other habitats. Only a few species were sighted more often in miscanthus than in other habitats, e.g. the marsh warbler Acrocephalus palustris; the reed bunting Emberiza schoeniclus; the whinchat Saxicola rubetra. The potential impact of expanded miscanthus cropping on bird communities in Central and Eastern Europe may diverge from predictions derived from studies based in Western Europe due to differing habitat preferences and bird densities between the regions. For a majority of farmland species, the crop may constitute only a suboptimal, supplementary habitat, with only a few birds potentially adapting to the exploitation of bioenergy plantations.

Pinching off syndrome in free-ranging white-tailed sea eagles (Haliaeetus albicilla) in Europe: frequency and geographic distribution of a generalized feather abnormality.

Generalized feather abnormalities are rarely documented in free-living birds. Pinching off syndrome (POS) is a feather abnormality in which all remiges and retrices become malformed and are lost during the nestling stage, rendering the bird unable to fly. To determine the frequency of occurrence and geographic distribution of this syndrome in white-tailed sea eagles (Haliaeetus albicilla) in Europe, we sent questionnaires to ornithologists in 19 countries within the European range of this species. We also searched for reported cases of sea eagles with feather abnormalities that met the criteria of POS. Overall, 32 nestlings or fledglings with POS were identified between 1975 and 2006. The geographic distribution of cases was primarily restricted to 4 European countries: Germany (17 cases), Poland (11 cases), the Czech Republic (3 cases), and Great Britain (1 case). Eleven eagles from Germany and 2 eagles from the Czech Republic were examined clinically. In 15 birds in which sex was determined, 8 were female and 7 were male. From 2000 to 2005, the 5-year incidence of POS in white-tailed sea eagles in Germany was 3.5 cases per 1000 birds. Although the etiology of this syndrome in wild sea eagles is unknown, our results support a possible genetic cause.

Habitat preferences of two sparrow species are modified by abundances of other birds in an urban environment.

Every species has certain habitat requirements, which may be altered by interactions with other co-occurring species. These interactions are mostly ignored in predictive models trying to identify key habitat variables correlated with species population abundance/occurrence. We investigated how the structure of the urban landscape, food resources, potential competitors, predators, and interaction between these factors influence the abundance of house sparrow Passer domesticus and the tree sparrow P. montanus in sixty 25 ha plots distributed randomly across residential areas of the city of Poznan (Poland). The abundance of the house sparrow was positively correlated with the abundance of pigeons but negatively correlated with human-related food resources. There were significant interaction terms between abundances of other urban species and habitat variables in statistical models. For example, the abundance of house sparrow was negatively correlated with the abundance of corvids and tree sparrows but only when food resources were low. The abundance of tree sparrows positively correlated with density of streets and the distance from the city center. The abundance of this species positively correlated with the abundance of corvids when food resources were low but negatively correlated at low covers of green area. Our study indicates that associations between food resources, habitat covers, and the relative abundance of two sparrow species are altered by the abundance of other urban species. Competition, niche separation and social facilitation may be responsible for these interactive effects. Thus, biotic interactions should be included not only as an additive effect but also as an interaction term between abundance and habitat variables in statistical models predicting species abundance and occurrence.