Search results for "bird"

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…

Unconditional adoption rules out the need for parent–offspring recognition in a single‐brooded colonial seabird

2021

Parent–offspring recognition (POR) is fundamental in colonial birds when the potential intermingling of chicks is higher due to the large number and proximity of nests. In species with isolated nests, where chick presence in the nest is strong contextual evidence of kinship, there might be circumstances when the parent might doubt the identity of the chick, but not enough to reject it. Olfactory-based recognition of conspecifics and nest sites in birds has gained strong evidence suggesting a potential role of olfaction in POR. Despite that, there are no studies testing it. We used Scopoli's shearwater (Calonectris diomedea) as model colonial single-brooded species with a developed olfactory…

Warblers from the New vs Old World: Quantifying selection by examining behaviours in two brood parasitism systems

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

Domain‐specific neural networks improve automated bird sound recognition already with small amount of local data

2022

1. An automatic bird sound recognition system is a useful tool for collecting data of different bird species for ecological analysis. Together with autonomous recording units (ARUs), such a system provides a possibility to collect bird observations on a scale that no human observer could ever match. During the last decades, progress has been made in the field of automatic bird sound recognition, but recognizing bird species from untargeted soundscape recordings remains a challenge. 2. In this article, we demonstrate the workflow for building a global identification model and adjusting it to perform well on the data of autonomous recorders from a specific region. We show how data augmentatio…

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…