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Olomouc, Czech Republic

Turcokova L.,Ornitologicka Laborator
Sylvia | Year: 2011

All bird species have their own species-specific vocal performance. On the basis of this signal, individuals are able to recognise each other and avoid thus interspecific hybridisation. When populations belonging to one species are isolated by space or time, song divergence occurs at different geographic scales. Individual song parameters can be influenced by different ecological conditions. The resulting divergence may become genetically fixed. The song is also shaped by different social interactions. Special song patterns can be maintained through learning processes and are influenced by the timing of song learning and the natal dispersal of young birds. Many studies focusing on song variability in a number of bird species have brought about inconsistent results. The aim of this review is to summarise these results, look at the factors influencing song variability, focus on dialect formation, and its maintenance in time and space.

Kral M.,Valsuv Dul 504 | Adamik P.,Vlastivedne Muzeum v Olomouci | Adamik P.,Ornitologicka Laborator | Krause F.,Bretislavova 8 | And 9 more authors.
Sylvia | Year: 2011

Covering a time span 1953-2009, we summarize all available data on arrival dates, breeding phenology and reproduction of the Collared Flycatcher (Ficedula albicollis) in Moravia, the eastern part of the Czech Republic. Mean arrival date of males was April 18 (mean annual range April 6 to April 24). Between years, the first-egg-laying dates were in a range of April 24 to May 15, mean date being May 3. Mean first-egg-laying date in all clutches, excluding replacement clutches, was May 7 (range April 30 to May 18). Mean clutch size was 6.40 ± 0.72 eggs (SD), between years in a mean range 5.80 - 6.60 eggs. In the warm regions of Moravia the mean first-arrival dates of males were 4.2 days earlier than in moderately warm regions. Similarly, the first-egg-laying dates and mean first-egg-laying dates were 3.9 and 4.8 days earlier in the warm regions, respectively. Mean clutch size was by 0.17 egg larger in the warm regions. Since the early 1980s we have found significant long-term trends towards earlier arrival and laying dates and increasing clutch size in the Collared Flycatcher in both climate regions of Moravia.

The paper describes an unusual case of fatal injury of a Skylark (Alauda arvensis) hatchling by a ground beetle (Carabidae, probably of the genus Pterostichus). The beetle bite caused necrosis and apostasy of the chick's right tarsometatarsus. The young Skylark without a major part of its right leg survived due to parental care until his healthy sibling fledged (eight days later).

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