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Boštjan Deberšek and Dejan Bordjan

Abstract

Between September 2014 and August 2015, 32 systematic surveys of waterbirds were carried out in 10-day periods in the area of Šaleška Lakes. The main objectives of the surveys were to establish the birds’species structure and abundance as well as to assess the area’s significance for their breeding, migration and overwintering. A total of 8927 individuals belonging to 53 species were recorded. Most species were observed at the end of March (27), whereas the highest number of individuals were registered in early January (535). The lowest number of individuals were counted in May (73). Mallard Anas platyrhynchos, Great Crested Grebe Podiceps cristatus, Mute Swan Cygnus olor and Grey Heron Ardea cinerea were observed during all counts. An additional 10 species were registered in at least 50% of the 10-day periods. The highest number of individuals (2891) and species (34) were counted at Lake Šoštanj, the highest number of individuals (295) and species (21) in a single 10-day survey period at Lake Gaberke. Most nestlings and nesting species were recorded at Lake Velenje. The majority of species occurred on all lakes within the research area, while some of them frequented certain lakes only exceptionally. The lowest numbers of birds were observed in central parts of all major waterbodies, particularly at Lake Velenje. Distribution of waterbirds at Šaleška Lakes is greatly influenced by the presence and distribution of people along them, as well as by the depth and riparian vegetation of the lakes and number of suitable roosting places. The number of breeding species is higher than in the 1994-2003 period. Little Bittern Ixobrychus minutus, Kingfisher Alcedo atthis and Great Reed Warbler Acrocephalus arundinaceus are new breeders for the area. The most abundant breeder is the Mallard with up to 16 pairs. The area’s breeders of the greatest conservation concern are the Little Bittern, Great Reed Warbler and Reed Warbler Acrocephalus scirpaceus, with the latter boasting the greatest share of the national breeding population (5%) in the area. Generally, most species occur during the migration season, although none of them in the numbers of conservation concern. Among the 33 waterbird species observed during the International Waterbird Censuses, five were recorded in all 18 years. Pochard Aythya ferina and Coot Fulica atra are of the greatest conservation concern, whereas the greatest share of the national population is reached by the Coot and Great Crested Grebe. In spite of the fact that the numbers of overwintering waterbirds in Slovenia are increasing, their numbers are declining at Šaleška Lakes. Among the 13 species recorded during more than ten International Waterbird Counts in the area researched, eight species are experiencing negative trends.

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Katja Logar and Luka Božič

Abstract

Between April 2007 and April 2008, 40 systematic waterbird counts were conducted on the Drava River between Lake Maribor and the Melje Dam (length 8.5 km, area 155 ha) to determine the specific composition, abundance and seasonal dynamics of bird occurrence. Between October and May, counts were conducted every week, whereas between June and September they were carried out once every two weeks. In total, 26,803 individuals of 30 species were counted. The number of waterbirds and diversity of species were the highest from late December to late February, when more than 1,000 individuals were regularly present in the area. Waterbirds were distributed along the river unequally, with the highest number of birds present yearround in the city centre and in the first counting sector of Lake Maribor. The Mallard Anas platyrhynchos and Mute Swan Cygnus olor were recorded during every count, while occurrence frequency was greater than 50% in another 10 species. Dominant species in terms of percentage composition were Mallard, Black-headed Gull Chroicocephalus ridibundus, Coot Fulica atra, Mute Swan, Pochard Aythya ferina and Tufted Duck Ay. fuligula. Mute Swan and Mallard were the only breeding waterbirds in the study area. Both the total number of waterbirds and the highest daily total in the first two counting sectors were greater between October and March 1992/93 than in our study. The decline in numbers was the greatest for Mallard, Pochard and Tufted Duck, while an increase was noted in Mute Swan and Yellow-legged / Caspian Gull Larus michahellis / cachinnans. The total number of waterbirds and the number of some species in the study area were significantly higher than expected solely based on its length compared to the length of the lowland Drava in Slovenia (125.7 km). The study area is conservationally important for Pochard, Tufted Duck and Black-headed Gull

Open access

Dejan Bordjan and Luka Božič

Bulgarian Wetlands. - Pensoft Publishers, Sofia - Moscow. Mihelič, T. & Genero, F. (2005): Occurrence of Griffon Vulture Gyps fulvus in Slovenia in the period from 1980 to 2005. - Acrocephalus 26 (125): 73-79. MKGP (2005): Kataster dejanske rabe kmetijskih zemljišč - digitalni sloj. - Ministrstvo Republike Slovenije za kmetijstvo, gozdarstvo in prehrano, Ljubljana. Mohar, D. (2001): Čopasta čaplja Ardeola ralloides . - Acrocephalus 22 (106/107): 121. Newton, I

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Dejan Bordjan

, Y., Schulze, C.H., Pavličev, M. & Wichmann, G. (2009): Spring migration dynamics and sex-specific patterns in stopover strategy in the Wood sandpiper Tringa glareola . - Journal of Ornithology 150 (2): 313-319. Omerzel, M. (2008): Žerjav Grus grus . - Acrocephalus 29 (137): 113. Panuccio, M. & Agostini, N. (2010): Timing, age classes and water-crossing behaviour of Black Kites ( Milvus migrans ) during spring migration across the central Mediterranean. - The ring 32 (1/2): 55-61. Ploj, A. (2009): Plevica Plegadis

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Lenka Bobuľská, Dagmar Macková, Radovan Malina and Lenka Demková

, 44, 701–712. Crawley, M.J. (1986) The population biology of invaders. Philos Trans R Soc B, 314, 711–729. Csontos, P. (1986) Dispersal and establishment of Impatiens parviflora, an introduced plant in a hardwood forest. Abstracta Botanica, 10, 341–348. Čuda, J., Skálová, H., Janovský, Z. & Pyšek, P. (2014) Habitat requirements, short-term population dynamics and coexistence of native and invasive Impatiens species: a field study. Biol Invasions, 16, 177–190. Chmura, D. (2006) Wpływ gatunków inwazyjnych na różnorodnosc fitocenotyczna

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Jozef Takáč

. - Ingw ers en, J. - Chen, X. - Zhang , F. - MÜll er, T. - Römh eld , V. 2010. Modelling water dynamics with DNDC and DAISY in a soil of the North China Plain: A comparative study. In Environmental Modelling & Software, vol. 25 , pp. 583-601. DOI: 10.1016/j.envsoft.2009.09.003. Lapin , M. - Fašk o, P. - Kveták , Š. 1988. Metodický predpis 3-09-1/1. Klimatické normály [Methodological prescription 3-09-1/1. Climate normals]. Bratislava : SHMÚ. 25 p. LAPIN, M. - FAŠKO, P. - MELO, M. - ŠŤASTNÝ, P. - TOMLAIN, J. 2002. Klimatické oblasti

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Katarzyna Marciszewska, Andrzej Szczepkowski, Anna Otręba, Lidia Oktaba, Marek Kondras, Piotr Zaniewski, Wojciech Ciurzycki and Rafał Wojtan

R eferences Bailey, K.L, Mupondwa, E.K. 2006. Developing microbial weed control products: commercial, biological and technological considerations. In: Handbook of Sustainable Weed Management (eds.: H.P. Singh, D.R. Batish, R.K. Kohli), The Haworth Press, Binghamton, NY, 431–473. Becker, E., Shamoun, S.F., Hintz, W.E. 2005. Efficacy and environmental fate of Chondrostereum purpureum used as a biological control for red alder ( Alnus rubra ). Biological Control , 33, 269–277. Bijak, Sz., Czajkowski, M., Ludwisiak, L. 2014. Occurrence of black

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Maciej Harat, Andrzej Lebioda, Judyta Lasota and Roman Makarewicz

uncertain. We therefore sought to identify factors that predispose to edema formation after SRS and assess edema formation and resolution dynamics. Patients and methods One hundred and three patients undergoing 111 SRS procedures were treated in the Oncology Centre in Bydgoszcz between January 2008 and October 2012. The study population had a heterogeneous set of histopathological diagnoses: 34 (29%) arteriovenous malformations (AVMs), 38 (35%) meningiomas, 16 (15%) metastatic tumors, 16 (15%) neuromas, 3 (3%) cavernous angiomas, 2 (2%) anaplastic astrocytomas, and

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P.K. Dutta and O.P. Mishra

, Symptoms of instability in a system of earthquake-prone faults, Physica, D 77. pp. 193–199. Korvin, G. (1992), Fractal Models in the Earth Sciences, Elsevier, 396 pp. 1-17. Laughlin, R.B., and Joannopoulos, J.D. (1978), Effect of second-nearest-neighbor forces on the vibrations of amorphous SiO2. Physics Reviews B 17, pp. 2790–2792. Matcharashvili, T. and Ghlonti, E. (2002), Detecting differences in dynamics of small earthquakes temporal distribution before and after large events, Computers & Geosciences 28, 693-700. Mishra, O. P., Zhao, D

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Paweł Bereś and Rafał Sionek

J. 2009. [Occurrence of western corn rootworm ( Diabrotica virgifera Le Conte) in the south-western part of Poland]. Prog. Plant. Protection/Post. Ochr. Roślin 49 (4): 1681-1685. [in Polish with English summary] EPPO Standards, European and Mediterranean Plant Protection Organization. 2004. Diagnostic protocols for regulated pests. Diabrotica virgifera. PM 7/36(1). Bull. OEPP/EPPO, 34: 289-293. EPPO, European and Mediterranean Plant Protection Organization. 2010. Present situation of Diabrotica virgifera in