Red-backed Shrike (Lanius collurio) Science Article 6 abstract We investigated the stable isotope signatures (d15N and d13C) of greater feather covers of male and female Red-backed Shrikes (Lanius collurio) of a southern German population. Male and female birds did not differ in their isotope signatures, thus revealing similar winter grounds for both sexes Hans Jakober, […]
Category: Passeriformes
Using microsatellites to obtain genetic structure data for Red-backed Shrike (Lanius collurio): a pilot study
Red-backed Shrike (Lanius collurio) Science Article 1 abstract The declining Western European population of the Red-backed Shrike (Lanius collurio) is hypothesised to be a part of the same metapopulation as the Dutch population, at the edge of the contracting western range. Due to habitat fragmentation the Dutch population is mainly situated in the Bargerveen reserve […]
Which method is most suitable for censusingbreeding populations of red-backed (Laniuscollurio) and great grey (L. excubitor) shrikes?
Red-backed Shrike (Lanius collurio) Science Article 3 abstract Up to now, studies have shown that it is very difficult to estimate accurate numbers of shrike(Lanius spp) breeding pairs. During our shrike biology research in Western Poland this problemwas evident. Actual breeding pair numbers were derived from a combination of specialcounts in the pre-breeding period, intensive […]
Eggshell patterning in the Red-backed Shrike Lanius collurio: relation toegg size and potential function
Red-backed Shrike (Lanius collurio) Science Article 5 abstract Despite numerous studies on avian eggs, the function of eggshell patterning remains largely unknown. Using a museum collection of Red-backed Shrike clutches, we estimated the repeatability of characteristics describing the intensity and contrast of egg pigmentation, as well as egg size and shape. Digitalized photographs of eggs […]
Red-backed Shrike (Lanius collurio) nest performance in a declining British population: a comparison with a stable population in Poland
Red-backed Shrike (Lanius collurio) Science Article 7 abstract We compare the breeding ecology of Red-backed Shrike Lanius collurio prior to its effective extinction (in 1990) as a breeding bird in the UK with that of a stable population in southwestern Poland. We use breeding performancedata derived from theUK and Polish Nest Record Schemes. Although theclutch […]
Blood parasites, reproduction and sexual selection in the red-backed shrike (Lanius collurio)
Red-backed Shrike (Lanius collurio) Science Article 2 abstract We investigated the occurrence of blood parasites on the red-backed shrike Lanius collurio during a three-year study in southern Czech Republic. Selected traits of shrike body morphology, male plumage and reproduction were studied with respect to the presence and intensity of h matozoan infection in blood samples […]
Is the nominate subspecies of the Common Crossbill Loxia c. curvirostra polytypic? I. Morphological differences among years at a single site.
Red Crossbill (Loxia curvirostra) Science Article 1 abstract The discovery of discrete vocal types of Common Crossbill in Western Europe opens the possibility that the nominate subspecies Loxia c. curvirostra in fact consists of a group of cryptic, vocally differentiated and reproductively isolated sibling species, reflecting a similar situation in North America. We compared measures […]
Population fluctuations of Siskins Carduelis spinus,Common Crossbills Loxia curvirostra, and Citril FinchesCarduelis citrinella in relationship to flowering intensityof spruce Picea abies
Red Crossbill (Loxia curvirostra) Science Article 2 abstract Annual population abundances from 1992 to 2002 of Siskins Carduelis spinus, CommonCrossbills Loxia curvirostra and Citril Finches Carduelis citrinella were studied in relationto flowering intensity of spruce Picea abies.We used point countmethod to study thechanges in abundance of the three species in the Northern Black Forest (southwest […]
Prothonotary Warbler Nest Success and VegetationCharacteristics in a Fragmented Oklahoma Landscape
Prothonotary Warbler (Protonotaria citrea) Science Article 2 abstract In 2003, I studied the relationship between prothonotary warbler (Protonotaria citrea)nest success and vegetation characteristics in a fragmented Oklahoma landscape. Fortynest boxes were monitored for reproductive success and vegetation characteristics weremeasured at nest boxes and 40 random points within the same stands. Thirty-five successfulnests fledged a mean […]
Retaliatory mafia behavior by a parasitic cowbirdfavors host acceptance of parasitic eggs
Prothonotary Warbler (Protonotaria citrea) Science Article 3 abstract Why do many hosts accept costly avian brood parasitism evenwhen parasitic eggs and nestlings differ dramatically in appearancefrom their own? Scientists argue that evolutionary lag orequilibrium can explain this evolutionary enigma. Few, however,consider the potential of parasitic birds to enforce acceptance bydestroying eggs or nestlings of hosts […]