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1

Factors affecting temporal dynamics of avian assemblages in a heterogeneous landscape

100%
Tworek S.
Acta Ornithologica
|
2004
|
tom 39
|
nr 2
The influence of the characteristics of habitat fragments on the dynamics of avian communities and the effect that fragments of different sizes have on the stability of the breeding species composition, and also on local extinction, colonisation and turnover rates were studied in an agricultural landscape in southern Poland. The fragments included various habitat types that differed from the matrix. Breeding birds were surveyed using the territory mapping method to assess turnover. Species composition depended on both the spatial structure of a fragment and the features of its surroundings. Local declines and appearances of species had a similar influence on the turnover in all size classes of the fragments. Species that contributed most to the total turnover were: Lanius collurio, Phasianus colchicus, Anas platyrhynchos, Emberiza schoeniclus, Columba palumbus and Sylvia communis. However, there were differences among species contributing most to the turnover according to area size classes. Heterogeneous habitats in a mosaic-like, agricultural landscape do not function as islands. The existence of species in an area with such a level of habitat patchiness can be related primarily to habitat quality, mainly because of poor isolation and the high permeability of isolating habitats.
2

O roznorodnosci biologicznej w kontekscie dzialan na rzecz ochrony przyrody

100%
Tworek S.
Wszechświat
|
2007
|
tom 108
|
nr 07-09
196-201
3

Charakterystyka zgrupowan ptasich w siedliskach wyspowych krajobrazu rolniczego i reakcje ptakow na zmiany w srodowisku.

100%
Tworek S.
Działalność Naukowa PAN. Wybrane Zagadnienia
|
2001
|
tom 12
74-76
4

Czynniki wplywajace na wystepowanie ptakow legowych w krajobrazie rolniczym poludniowej Polski

100%
Tworek S.
Studia Naturae
|
2010
|
tom 58
1-180
5

Znaczenie zroznicowania siedlisk dla awifauny legowej terenow rolniczych w dolinie Rudawy kolo Krakowa

100%
Tworek S.
Chrońmy Przyrodę Ojczystą
|
1998
|
tom 54
|
nr 2
39-52
6

Factors affecting bird species diversity on a local scale: a case study of a mosaic landscape in Southern Poland

100%
Tworek S.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 4
The main objective of this paper was to investigate factors that affect bird species diversity at local spatial scales including the role of habitat heterogeneity. The studies were carried out in a mosaic landscape of southern Poland, in habitat fragments, each described by variables which characterised the size of the plot and its spatial structure, including vegetation. A species diversity index was then calculated for each plot using Shannon-Wiener index, based on count of nesting birds obtained through territory mapping method. Correspondence analysis (CA) was then used to illustrate relationships between groups of plots of different scopes of species diversity and the measured characteristics of the plots. The high diversity among birds was found to be primarily connected with an increase in the proportion of old forest, whereas the diversity decreased with an increase in the proportion of ‘farmland’ (including meadows and pastures). Other significant effects on the changes in species diversity were exerted by the degree of density in the herb layer and the tree canopy layer, as well as by the presence of wetlands. The localscale inertia in the heterogeneous-type habitats results primarily from the differences in quality and structure of the plot, which reflect their position between the ‘forest’ – ‘non-forest’ gradient. In the studied range of sizes (0.2–40 ha), the size of a given plot is of lesser significance than that of the vegetation structure. All the variables which represent potential effects upon the local-scale diversity of birds, and the suitability of CA are discussed against the background of the results of this study and available literature data.
7

Cluster-based approach for identifying avian life-history groups for use in ecological monitoring

100%
Tworek S.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 1
Almost ‘since ever’ ecologists have made attempts at the generalization of various site-specific, species-specific and timespecific situations, including different classifications of species, based on different principles and prepared for different purposes. This paper, presenting a conceptual model for selecting species of similar life-history pattern to other species and providing an example using birds as a model system, represents that current in the ecology. All bird species regarded as nesting in a given area of the mosaic landscape in southern Poland were described with respect to nine variables (nest type, nest location, food habits, place and way of foraging, migration status, number of broods, clutch size, incubation and fledging periods), grouped into 43 categories. Cluster analysis was then used to distinguish objectively species displaying similar life history traits and environmental adaptations into unique life-history ‘strategies’. The results of an exemplary analysis of variability in the density, domination, number of species and turnover rate in particular strategies, depending on the size of study plots, their structure, degree of isolation and the characteristic features of their surroundings, using regression and canonical correlation techniques, indicate the suitability of this approach to testing detailed hypotheses connected e.g. with studies on the response of species to different habitat conditions. The methods applied allow one to distinguish, in an objective way, the groups of species displaying similarities with respect to life history traits and environmental adaptations, in spite of the fact that the method of describing variables in cluster analysis may determine a different allocation of species to groups. A model, as described, could allow conservation principles to be developed for species of similar distribution, ecological feature or life history; especially for those species which face with population declines and for which no previous patterns have been established.
8

Breeding bird communities in relation to different habitat islands

100%
Tworek S.
Nature Conservation
|
2001
|
tom 58
9

The projected Natura 2000 network in Poland: a need for supplementing the governmental list of proposed sites of community importance

63%
Makomaska-Juchiewicz M., Tworek S.
Nature Conservation
|
2005
|
tom 61
65-75
10

Rzadkie gatunki ptakow obserwowane w okolicy Padwi 1983-1990 [woj.tarnobrzeskie]

63%
Tworek S., Hudy A.
Badania nad Ornitofauną Ziemi Przemyskiej
|
1997
|
tom 05
47-55
11

Natura 2000. Projektowana siec Natura 2000 w Polsce a krajowy system obszarow chronionych

63%
Makomaska-Juchiewicz M., Tworek S.
Parki Narodowe
|
2003
|
nr 4
2-9
12

Rola sieci Natura 2000 w ochronie europejskiego dziedzictwa przyrodniczego

51%
Cierlik G., Makomaska-Juchiewicz M., Tworek S.
Przegląd Przyrodniczy
|
2005
|
tom 16
|
nr 1-2
3-13
13

The model for assessing of natural, landscape, scientific and educational values of national parks in Poland

51%
Tworek S., Makomaska-Juchiewicz M., Mroz W.
Nature Conservation
|
2004
|
tom 60
13-22
14

Intrapopulation variation of egg size in the White Stork [Ciconia ciconia] in Southern Poland

51%
Profus P., Tryjanowski P., Tworek S., Zduniak P.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 1
White Stork (Ciconia ciconia) eggs were studied in Upper Silesia, Southern Poland. The measurements of eggs – their length, breadth, volume and elongation index were collected for 95 nests in years 1974–2002, and repeatability of these measurements was computed. Mean clutch size was 4.05 ± 0.82. Mean egg measurements were: 72.10 ± 2.18 mm, 52.19 ± 1.47 mm, 100.49 ± 6.92 cm³ and 1.38 ± 0.05, for length, breadth, volume and elongation index, respectively. Coefficients of variation for clutch means ranged from 1.68 (breadth) to 4.37 (volume). Mean repeatability estimates were 0.53, 0.68, 0.63, 0.58 for length, breadth, volume and elongation index, respectively. The results obtained suggest that one should expect relatively low or intermediate heritability of egg dimensions in population studied.
15

Hipotermia u ptakow w warunkach arktycznej zimy

50%
Tworek S.
Wszechświat
|
1997
|
tom 98
|
nr 06
152-153
16
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Helix pomatia - protection and exploitation in the Malopolska region

45%
Dyduch-Falniowska A., Makomaska-Juchiewicz M., Perzanowska-Sucharska J., Tworek S., Zajac K.
Folia Malacologica
|
2000
|
tom 08
|
nr 4
17

Występowanie wybranych, obcych geograficznie gatunków roślin na terenie Wolińskiego Parku Narodowego i jego otuliny

45%
Perzanowska J., Korzeniak J., Krol W., Cierlik G., Tworek S.
Chrońmy Przyrodę Ojczystą
|
2016
|
tom 72
|
nr 5
18

Siec obszarow chronionych Emerald

39%
Dyduch-Falniowska A., Tworek S., Makomaska-Juchiewicz M., Perzanowska J., Cierlik G., Mroz W.
Chrońmy Przyrodę Ojczystą
|
2002
|
tom 58
|
nr 4
60-70
19

Ectopic bone formation after treatment with colchicine

33%
Tworek K., Solak K., Janeczek A., Niedzwiedzki T., Tabarowski Z., Dabrowski Z., Schoutens A., Tworek S.
Folia Biologica
|
2010
|
tom 58
|
nr 1-2
125-133
20

Conservation of farmland birds faces different challenges in Western and Central-Eastern Europe

24%
Tryjanowski P., Hartel T., Baldi A., Szymanski P., Tobolka M., Herzon I., Golawski A., Konvicka M., Hromada M., Jerzak L., Kujawa K., Lenda M., Orlowski G., Panek M., Skorka P., Sparks T. H., Tworek S., Wuczynski A., Zmihorski M.
Acta Ornithologica
|
2011
|
tom 46
|
nr 1
Birds are commonly used as an example of the strongly declining farmland biodiversity in Europe. The populations of many species have been shown to suffer from intensification of management, reduction of landscape heterogeneity, and habitat loss and fragmentation. These conditions particularly dominate farmland in the economically well developed countries of Western Europe. Currently, the farmland environment in Central-Eastern Europe is generally more extensive than in Western Europe and a larger proportion of people still live in rural areas; thus generating different conditions for birds living in agricultural areas. Furthermore, the quasi-subsistence farming in much of Central-Eastern Europe has resulted in agricultural landscapes that are generally more complex than those in Western Europe. To protect declining bird populations living in farmland, detailed knowledge on both species and communities is necessary. However, due to scientific tradition and availability of funding, the majority of studies have been carried out in Western Europe. In consequence this provokes a question: are findings obtained in western conditions useful to identify the fate of farmland bird biodiversity in Central-Eastern Europe? Therefore, the major goal of this paper is to highlight some local and regional differences in biodiversity patterns within EU farmland by comparing intensive agricultural landscapes with more extensive ones. More specifically, we aim to outline differences in agricultural landscapes and land use history in the two regions, use farmland birds to provide examples of the differences in species dynamics and species-habitat interactions between the two regions, and discuss possible social and ecological drivers of the differences in the context of biodiversity conservation. Factors governing spatio-temporal dynamics of farmland bird populations may differ in intensive and extensive landscapes as illustrated here using the Grey Partridge Perdix perdix and the Red-backed Shrike Lanius collurio as examples. The unevenness of farmland bird studies distribution across Europe was also presented. We call for more emphasis on pluralism in furthering both pan-European research on farmland bird ecology and conservation strategies. We also highlight some features specific to Central-Eastern Europe that merit consideration for the more efficient conservation of farmland birds and farmland biodiversity across Europe.
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