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Pavel V.,Katedra Zoologie A Ornitologicka Laborator PrF | Chutny B.,Malinova 27
Sylvia | Year: 2010

We present an interesting source of colour leg rings for birds - HAMA beads. These inexpensive beads are available in toy stores, they are made from durable plastic and easy to apply. The product is imported to the Czech Republic by Lowlands International (http://www.lowlands.cz). The rings are lost by the birds in the same rate as the standard professional colour rings (the interseasonal loss rate tested in the Bluethroat Luscinia svecica svecica was 3.17 versus 2.93%) and their colours are mostly resistant to wear (except for brown and orange). Their major limitation is that only two sizes are available (HAMA MIDI and HAMA MAXI, with inside diameters of 2.8 and 6 mm, respectively).

Matysiokova B.,Katedra Zoologie A Ornitologicka Laborator PrF
Sylvia | Year: 2010

Incubation feeding is a behaviour whereby the male feeds his mate during incubation. This behaviour occurs in several groups of birds, most often in hornbills, raptors, owls, parrots and songbirds. This review presents all hypotheses proposed to explain the function of incubation feeding and summarises published studies dealing with this behaviour in birds. First, I summarise the factors that have an influence on the rate of incubation feeding. These include territory quality, female condition, male characteristics, risk of predation, ambient temperature, time of day, date, clutch size, age of the clutch and social structure. Moreover, there are factors which are affected by incubation feeding. These include nest attentiveness, risk of predation, female condition, length of incubation period and reproductive success. Incubation feeding was mostly negatively correlated with ambient temperature and the risk of nest depredation and positively with female nest attentiveness. However, most of the studies included in this review are correlational and thus it is difficult to infer causal relationships between individual behavioural, phenotypic, and environmental characteristics.

Kolecek J.,Katedra Zoologie A Ornitologicka Laborator PrF | Paclik M.,Katedra Zoologie A Ornitologicka Laborator PrF | Weidinger K.,Katedra Zoologie A Ornitologicka Laborator PrF | Reif J.,Katedra Zoologie A Ornitologicka Laborator PrF
Sylvia | Year: 2010

We analysed the point-count data on birds in two floodplain forests in Central Moravia, Czech Republic (Království near the Grygov village and Žebračka near the Přerov town) in the years 2007 and 2008. We compared qualitative and quantitative characteristics of bird communities between the two sites and between two breeding seasons. We also searched for patterns in the number of counted birds in relation to time of the day and for relationship between habitat parameters and occurrence of birds. Finally, we discuss the methodological background of bird census techniques used in this study. In total, we found 68 bird species. More species were observed in the Království forest probably due to its larger area and higher habitat diversity. Mean species abundance on the occupied points was positively correlated with species occupancy. Point count is one of the most widely used census methods, but its potential, in terms of possible biological conclusions on bird communities, is not fully exploited by ornithologists. In this paper, we draw attention to several well-known but underused methods and analytical procedures, such as the rarefaction method for comparing species richness among sites, analysing bird-habitat relationship and estimating bird density from the point-count data.

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