Search results for "birds"
showing 10 items of 291 documents
Data from: First records of complete annual cycles in water rails Rallus aquaticus show evidence of itinerant breeding and a complex migration system
2020
In water rails Rallus aquaticus, northern and eastern populations are migratory while southern and western populations are sedentary. Few details are known about the annual cycle of this elusive species. We studied movements and breeding in water rails from southernmost Norway where the species occurs year-round. Colour-ringed wintering birds occurred only occasionally at the study site in summer, and vice versa. Geolocator tracks revealed that wintering birds (n = 10) migrated eastwards in spring to breed on both sides of the Baltic Sea, whereas a single breeding bird from the study site wintered in north Italy. Ambient light records of geolocator birds further indicated that all but one i…
The effect of hyperthyroidisation on the plumage of carnivorous birds
1931
Izvilkums no: Acta Zoologica, Stockholms högskola, Bd.11, 1930.
Sex-ratio of Skylark Alauda arvensis broods in relation to timing of breeding.
2006
4 pages; International audience; Capsule Earlier broods tend to be more male biased than later broods.
Effects of density, species interactions, and environmental stochasticity on the dynamics of British bird communities
2022
Our knowledge of the factors affecting species abundances is mainly based on time-series analyses of a few well-studied species at single or few localities, but we know little about whether results from such analyses can be extrapolated to the community level. We apply a joint species distribution model to long-term time-series data on British bird communities to examine the relative contribution of intra- and interspecific density dependence at different spatial scales, as well as the influence of environmental stochasticity, to spatiotemporal interspecific variation in abundance. Intraspecific density dependence has the major structuring effect on these bird communities. In addition, envi…
Movements of water rails from Norway-reference-data
2020
Lislevand T, Hahn S, Rislaa S, Briedis M. 2020. First records of complete annual cycles in water rails Rallus aquaticus show evidence of itinerant breeding and a complex migration system. J Avian Biol. doi:10.1111/jav.02595
Movements of water rails from Norway-tracks
2020
Lislevand T, Hahn S, Rislaa S, Briedis M. 2020. First records of complete annual cycles in water rails Rallus aquaticus show evidence of itinerant breeding and a complex migration system. J Avian Biol. doi:10.1111/jav.02595
Movements of water rails from Norway-light-levels
2020
Lislevand T, Hahn S, Rislaa S, Briedis M. 2020. First records of complete annual cycles in water rails Rallus aquaticus show evidence of itinerant breeding and a complex migration system. J Avian Biol. doi:10.1111/jav.02595
Innovative and Applied Research in Biology: Proceedings, Vol.1
2019
Projekti: ZD2016/AZ81 & ZD2016/AZ107
Invasive catfish in northern Italy and their impacts on waterbirds
2022
Predatory fish have occasionally been observed preying on birds, sometimes repeatedly, but few studies were able to unravel the overall significance of avian prey in fish diet and the predation impacts on bird populations. We used a control/impact study setup, using a Nature Reserve in northern Italy and a nearby control area, to determine: 1) the contribution of waterbirds to wels catfish diet in the Reserve, 2) the population density of wels catfish in the Reserve and control area and 3) the potential impacts of waterbird depredation by wels catfish on waterbird population trends. Our stable isotope Bayesian mixing model indicated that birds contributed 12.2% (5–27.9%, 50% confidence inte…
Predator proximity as a stressor in breeding flycatchers: mass loss, stress protein induction, and elevated provisioning.
2010
We investigated the physiological and behavioral consequences for prey breeding at different distances from a nesting predator. In a natural setting, Pied Flycatchers (Ficedula hypoleuca) made territory location decisions relative to established Sparrowhawk (Accipiter nisus) nests. From female flycatchers attending nests at different distances from Sparrowhawk nests, we measured body mass, blood stress protein (HSP60 and HSP70), and plasma immunoglobulin levels at the beginning (initial) and end (final) of the flycatcher breeding cycle, and provisioning rates during the nestling phase. We found that individuals breeding in closer proximity to Sparrowhawk nests, under higher perceived predat…