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Hradec Králové, Czech Republic

Porkert J.,Gocarova 542 | Hromadko M.,Halasova 824
Bird Study

Capsule Moult-breeding overlap in a male Common Redstart feeding a second brood may reflect time pressure to fit moult between the completion of breeding and migration. © 2012 British Trust for Ornithology. Source

Changes in the timing of reproduction of birds should provide good evidence of large-scale climate fluctuations. However, geographically separate populations of one species may respond variably. We analyzed egg laying dates of nine Eurasian populations of the Common Redstart Phoenicurus phoenicurus collected between 1969 and 2010. The timing of breeding differed greatly with latitude: the populations in the north started later, a breeding pair produced only one brood per season and the breeding season was shorter. Both yearly minimum and median firstegg laying dates advanced with increases in local air temperature, but the more northern populations had started at much lower temperatures, which was probably caused by the stimulation of photoperiod. The effects of large-scale climatic patterns (North Atlantic Oscillation, East Atlantic, Scandinavia/Eurasia-1) on the first-egg laying date were low. The egg laying dates advanced over the observed decades in all populations, although at a variable rate. Seven selected populations with the most complete data for the period 1986–2010 revealed an advancement of median first-egg laying dates of 0.11 days/year and 1.31 days/°C. The effect on minimum first-egg laying dates was smaller. The changes observed in two populations in Ural and western Siberia were smaller than those found in more westerly populations (Finland, central Europe). The timing of the start of breeding is probably less affected by climate change than the timing of spring migration, documented by European ornithological stations. © Dt. Ornithologen-Gesellschaft e.V. 2014. Source

Hogner S.,University of Oslo | Laskemoen T.,University of Oslo | Lifjeld J.T.,University of Oslo | Porkert J.,Gocarova 542 | And 5 more authors.
Ecology and Evolution

Mitochondrial DNA usually shows low sequence variation within and high sequence divergence among species, which makes it a useful marker for phylogenetic inference and DNA barcoding. A previous study on the common redstart (Phoenicurus phoenicurus) revealed two very different mtDNA haplogroups (5% K2P distance). This divergence is comparable to that among many sister species; however, both haplogroups coexist and interbreed in Europe today. Herein, we describe the phylogeographic pattern of these lineages and test hypotheses for how such high diversity in mtDNA has evolved. We found no evidence for mitochondrial pseudogenes confirming that both haplotypes are of mitochondrial origin. When testing for possible reproductive barriers, we found no evidence for lineage-specific assortative mating and no difference in sperm morphology, indicating that they are not examples of cryptic species, nor likely to reflect the early stages of speciation. A gene tree based on a short fragment of cytochrome c oxidase subunit 1 from the common redstart and 10 other Phoenicurus species, showed no introgression from any of the extant congenerics. However, introgression from an extinct congeneric cannot be excluded. Sequences from two nuclear introns did not show a similar differentiation into two distinct groups. Mismatch distributions indicated that the lineages have undergone similar demographic changes. Taken together, these results confirm that deeply divergent mitochondrial lineages can coexist in biological species. Sympatric mtDNA divergences are relatively rare in birds, but the fact that they occur argues against the use of threshold mtDNA divergences in species delineation. © 2012 The Authors. Source

Lambrechts M.M.,CNRS Center of Evolutionary and Functional Ecology | Adriaensen F.,University of Antwerp | Ardia D.R.,Franklin And Marshall College | Artemyev A.V.,Russian Academy of Sciences | And 52 more authors.
Acta Ornithologica

The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines. Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents. However, when comparing results across study sites the use of nestboxes may also introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. However, the use of nestboxes may also introduce an unconsidered and potentially significant confounding variable due to differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. Here we review to what extent the characteristics of artificial nestboxes (e.g. size, shape, construction material, colour) are documented in the 'methods' sections of publications involving hole-nesting passerine birds using natural or excavated cavities or artificial nestboxes for reproduction and roosting. Despite explicit previous recommendations that authors describe in detail the characteristics of the nestboxes used, we found that the description of nestbox characteristics in most recent publications remains poor and insufficient. We therefore list the types of descriptive data that should be included in the methods sections of relevant manuscripts and justify this by discussing how variation in nestbox characteristics can affect or confound conclusions from nestbox studies. We also propose several recommendations to improve the reliability and usefulness of research based on long-term studies of any secondary hole-nesting species using artificial nestboxes for breeding or roosting. Source

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