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Selected aspects of autumn migration of birds and bats over a mountain pass
Koukolíková, Anna ; Lučan, Radek (advisor) ; Cepák, Jaroslav (referee)
Mountain passes situated in mountains of east-western orientation serve as important bird and bat migration corridors. Due to the increased concentration of migranting individuals in both groups, mountain passes can be used to study various aspects of migratory ecology. Within the Czech Republic, the most important site of this type is Červenohorské sedlo in Jeseníky. In this thesis, selected aspects of autumn migration (composition of the migratory population, phenology, factors influencing its intensity) of birds and bats during the autumn season were compared. In addition, data usability was compared for a reliable determination of autumn phenology in selected model bird species based. The comparison was between standardized mist netting in the mountains and set of data obtained from faunistic observations throughout the Czech Republic. Data from mountain mist netting has proven to be a more reliable indicator of the timing of bird migration, mainly because most species fly directly and quickly over the mountains, while in low-level observations there is a risk of mixinglocal and migratory populations. Also the number of observed individuals in some cases reflects the interest in extreme late occurrences in many species, which are generally given more attention and are more frequently recorded...
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Which effects govern intensity and timing of bird migration?
Koukolíková, Anna ; Lučan, Radek (advisor) ; Peške, Lubomír (referee)
Avian migration is one of the most striking manifestations of environmental seasonality in areas with higher latitude and is therefore not surprising that the study of this phenomenon has attracted biologists since immemorial times. One of the interesting findings is the fact that the spring and autumn migration does not take place at all times with the same intensity, but in most species noticeable migration maxima (waves)can be observed, often present over large geographical areas. Such synchronicity in migration behaviour implies the existence of specific triggers that affect migratory species populations. The presented thesis summarizes the current state of knowledge of factors (e.g. climatic, lunar, solar etc.) affecting the timing and intensity of bird migration. Key words: migration ecology, Aves, climate
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