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Tuesday, 16 December 2014

What's new for 'birdRS' in PubMed: December 2014; Week 3

This message contains My NCBI what's new results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM).

Search: (bird[TIAB] OR songbird[TIAB]) NOT (flu[TIAB] OR influenza[TIAB] OR bird[AUTH]) AND (2014/04/01[PDAT]:2020/01/01[PDAT])

View complete results in PubMed (results may change over time).


PubMed Results

1. PLoS One. 2014 Dec 10;9(12):e114625. doi: 10.1371/journal.pone.0114625. eCollection 2014.

Sexual Dimorphism in the Early Embryogenesis in Zebra Finches.

Tagirov M1, Rutkowska J2.
Author information:
1Poultry Research Institute, Ukrainian Academy of Agrarian Sciences, Borky, Ukraine.
2Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland.

Abstract

Sex-specific gene expression before the onset of gonadogensis has been documented in embryos of mammals and chickens. In several mammalian species, differences in gene expression are accompanied by faster growth of pre-implantation male embryos. Here we asked whether avian embryos before gonadal differentiation are also sex-dimorphic in size and what genes regulate their growth. We used captive zebra finches (Taeniopygia guttata) whose freshly laid eggs were artificially incubated for 36-40 hours. Analyses controlling for the exact time of incubation of 81 embryos revealed that males were larger than females in terms of Hamburger and Hamilton stage and number of somites. Expression of 15 genes involved in cell cycle regulation, growth, metabolic activity, steroidogenic pathway and stress modulation were measured using RT-PCR in 5 male and 5 female embryos incubated for exactly 36 h. We found that in the presence of equal levels of the growth hormone itself, the faster growth of male embryos is most likely achieved by the overexpression of the growth hormone receptor gene and three other genes responsible for cell cycle regulation and metabolism, all of them located on the Z chromosome. Autosomal genes did not show sex-specific expression, except for the steroidogenic factor 1 which was expressed only in female embryos. To our knowledge this is the first report of sexual size dimorphism before gonadogenesis in birds. The finding suggests that faster growth of early male embryos is conserved through the mammalian and bird phyla, irrespective of their differential sex chromosome systems.
PMID: 25493645 [PubMed - as supplied by publisher]
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2. PLoS One. 2014 Dec 10;9(12):e114861. doi: 10.1371/journal.pone.0114861. eCollection 2014.

Composition of Bacterial Assemblages in Different Components of Reed Warbler Nests and a Possible Role of Egg Incubation in Pathogen Regulation.

Brandl HB1, van Dongen WF1, Darolová A2, Krištofík J2, Majtan J2, Hoi H1.
Author information:
1Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine Vienna, Savoyenstrasse 1a, 1160 Vienna, Austria.
2Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, 845 06 Bratislava, Slovakia.

Abstract

Bacteria play a central role in animal health. Yet, little is known about the acquisition of bacteria and the extent to which bacteria are acquired from different environmental sources. For example, bird nests host diverse bacteria associated with the eggs, nestlings and nesting material, but previous research has typically focussed on only a limited number of nest components at a time. It therefore remains unknown to what extent bacteria are transmitted between these components. Using both molecular and culture techniques, we characterised nest-associated bacterial assemblages throughout the entire nesting cycle of reed warblers by sampling bacteria on eggs before and during incubation, within nestling faeces, and on the nesting material of post-breeding nests. We found that bacterial assemblages clustered by nest component. Yet some overlap existed between nest components, suggesting that bacterial transmission across components is likely to occur. Eggs and nestlings from the same nest harboured more similar bacteria than expected by chance, suggesting an influence of environment or genetics on bacterial assemblages. Bacterial loads were not lower on incubated eggs. Instead, incubation was associated with a change in the structure of assemblages, including a decrease in potentially-harmful Gram-negative bacteria. In addition we show for the first time, that incubation is associated with the complete extinction of harmful haemolytic bacteria. Overall, our study appears to be the first to demonstrate differences in bacterial assemblages between bird nest components. In addition, we highlight the complexity of nest bacterial assemblages and provide new insights into the benefits of incubation.
PMID: 25493434 [PubMed - as supplied by publisher]
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3. PLoS One. 2014 Dec 10;9(12):e114557. doi: 10.1371/journal.pone.0114557. eCollection 2014.

Juvenile Osprey Navigation during Trans-Oceanic Migration.

Horton TW1, Bierregaard RO2, Zawar-Reza P3, Holdaway RN4, Sagar P5.
Author information:
1Department of Geological Science, University of Canterbury, Christchurch, New Zealand.
2Biology Department, University of North Carolina at Charlotte, Charlotte, NC, United States of America.
3Geography Department, University of Canterbury, Christchurch, New Zealand.
4School of Biological Science, University of Canterbury, Christchurch, New Zealand.
5National Institute of Water and Atmospheric Research, Christchurch, New Zealand.

Abstract

To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus) are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old) of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.
PMID: 25493430 [PubMed - as supplied by publisher]
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4. Ecohealth. 2014 Dec 10. [Epub ahead of print]

Molecular Epidemiology of Avian Malaria in Wild Breeding Colonies of Humboldt and Magellanic Penguins in South America.

Sallaberry-Pincheira N1, Gonzalez-Acuña D, Herrera-Tello Y, Dantas GP, Luna-Jorquera G, Frere E, Valdés-Velasquez A, Simeone A, Vianna JA.
Author information:
1Laboratorio Fauna Australis, Departamento de Ecosistemas y Medio Ambiente, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile.

Abstract

Avian malaria is a disease caused by species of the genera Haemoproteus, Leucocytozoon, and Plasmodium. It affects hundreds of bird species, causing varied clinical signs depending on the susceptibility of the host species. Although high mortality has been reported in captive penguins, limited epidemiological studies have been conducted in wild colonies, and isolated records of avian malaria have been reported mostly from individuals referred to rehabilitation centers. For this epidemiological study, we obtained blood samples from 501 adult Humboldt and 360 adult Magellanic penguins from 13 colonies throughout South America. To identify malaria parasitaemia, we amplified the mtDNA cytochrome b for all three parasite genera. Avian malaria was absent in most of the analyzed colonies, with exception of the Punta San Juan Humboldt penguin colony, in Peru, where we detected at least two new Haemoproteus lineages in three positive samples, resulting in a prevalence of 0.6% for the species. The low prevalence of avian malaria detected in wild penguins could be due to two possible causes: A low incidence, with high morbidity and mortality in wild penguins or alternatively, penguins sampled in the chronic stage of the disease (during which parasitaemia in peripheral blood samples is unlikely) would be detected as false negatives.
PMID: 25492695 [PubMed - as supplied by publisher]
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5. Ecotoxicology. 2014 Dec 10. [Epub ahead of print]

Songbirds as sentinels of mercury in terrestrial habitats of eastern North America.

Jackson AK1, Evers DC, Adams EM, Cristol DA, Eagles-Smith C, Edmonds ST, Gray CE, Hoskins B, Lane OP, Sauer A, Tear T.
Author information:
1Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA, allyson.jackson@oregonstate.edu.

Abstract

Mercury (Hg) is a globally distributed environmental contaminant with a variety of deleterious effects in fish, wildlife, and humans. Breeding songbirds may be useful sentinels for Hg across diverse habitats because they can be effectively sampled, have well-defined and small territories, and can integrate pollutant exposure over time and space. We analyzed blood total Hg concentrations from 8,446 individuals of 102 species of songbirds, sampled on their breeding territories across 161 sites in eastern North America [geometric mean Hg concentration = 0.25 μg/g wet weight (ww), range <0.01-14.60 μg/g ww]. Our records span an important time period-the decade leading up to implementation of the USEPA Mercury and Air Toxics Standards, which will reduce Hg emissions from coal-fired power plants by over 90 %. Mixed-effects modeling indicated that habitat, foraging guild, and age were important predictors of blood Hg concentrations across species and sites. Blood Hg concentrations in adult invertebrate-eating songbirds were consistently higher in wetland habitats (freshwater or estuarine) than upland forests. Generally, adults exhibited higher blood Hg concentrations than juveniles within each habitat type. We used model results to examine species-specific differences in blood Hg concentrations during this time period, identifying potential Hg sentinels in each region and habitat type. Our results present the most comprehensive assessment of blood Hg concentrations in eastern songbirds to date, and thereby provide a valuable framework for designing and evaluating risk assessment schemes using sentinel songbird species in the time after implementation of the new atmospheric Hg standards.
PMID: 25492585 [PubMed - as supplied by publisher]
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6. PLoS Biol. 2014 Dec 9;12(12):e1002018. doi: 10.1371/journal.pbio.1002018. eCollection 2014.

Millisecond-scale motor encoding in a cortical vocal area.

Tang C1, Chehayeb D2, Srivastava K3, Nemenman I4, Sober SJ2.
Author information:
1Neuroscience Graduate Program, University of California, San Francisco, San Francisco, California, United States of America; Department of Biology, Emory University, Atlanta, Georgia, United States of America.
2Department of Biology, Emory University, Atlanta, Georgia, United States of America.
3Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States of America.
4Department of Biology, Emory University, Atlanta, Georgia, United States of America; Department of Physics, Emory University, Atlanta, Georgia, United States of America.

Abstract

Studies of motor control have almost universally examined firing rates to investigate how the brain shapes behavior. In principle, however, neurons could encode information through the precise temporal patterning of their spike trains as well as (or instead of) through their firing rates. Although the importance of spike timing has been demonstrated in sensory systems, it is largely unknown whether timing differences in motor areas could affect behavior. We tested the hypothesis that significant information about trial-by-trial variations in behavior is represented by spike timing in the songbird vocal motor system. We found that neurons in motor cortex convey information via spike timing far more often than via spike rate and that the amount of information conveyed at the millisecond timescale greatly exceeds the information available from spike counts. These results demonstrate that information can be represented by spike timing in motor circuits and suggest that timing variations evoke differences in behavior.
Free Article
PMID: 25490022 [PubMed - in process]
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7. Proc Natl Acad Sci U S A. 2014 Dec 8. pii: 201416252. [Epub ahead of print]

The birth of a dinosaur footprint: Subsurface 3D motion reconstruction and discrete element simulation reveal track ontogeny.

Falkingham PL1, Gatesy SM2.
Author information:
1Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, Hatfield AL97TA, United Kingdom; and Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912 pfalkingham@rvc.ac.uk.
2 Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912.

Abstract

Locomotion over deformable substrates is a common occurrence in nature. Footprints represent sedimentary distortions that provide anatomical, functional, and behavioral insights into trackmaker biology. The interpretation of such evidence can be challenging, however, particularly for fossil tracks recovered at bedding planes below the originally exposed surface. Even in living animals, the complex dynamics that give rise to footprint morphology are obscured by both foot and sediment opacity, which conceals animal-substrate and substrate-substrate interactions. We used X-ray reconstruction of moving morphology (XROMM) to image and animate the hind limb skeleton of a chicken-like bird traversing a dry, granular material. Foot movement differed significantly from walking on solid ground; the longest toe penetrated to a depth of ∼5 cm, reaching an angle of 30° below horizontal before slipping backward on withdrawal. The 3D kinematic data were integrated into a validated substrate simulation using the discrete element method (DEM) to create a quantitative model of limb-induced substrate deformation. Simulation revealed that despite sediment collapse yielding poor quality tracks at the air-substrate interface, subsurface displacements maintain a high level of organization owing to grain-grain support. Splitting the substrate volume along "virtual bedding planes" exposed prints that more closely resembled the foot and could easily be mistaken for shallow tracks. DEM data elucidate how highly localized deformations associated with foot entry and exit generate specific features in the final tracks, a temporal sequence that we term "track ontogeny." This combination of methodologies fosters a synthesis between the surface/layer-based perspective prevalent in paleontology and the particle/volume-based perspective essential for a mechanistic understanding of sediment redistribution during track formation.
PMID: 25489092 [PubMed - as supplied by publisher]
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8. Mol Ecol. 2014 Dec 9. doi: 10.1111/mec.13039. [Epub ahead of print]

MHC variation reflects the bottleneck histories of New Zealand passerines.

Sutton JT1, Robertson BC, Jamieson IG.
Author information:
1Allan Wilson Centre for Molecular Ecology and Evolution, Department of Zoology, University of Otago, New Zealand; Department of Biology, University of Hawai'i at Mānoa, USA.

Abstract

Most empirical evidence suggests that balancing selection does not counter the effects of genetic drift in shaping post-bottleneck MHC genetic diversity when population declines are severe or prolonged. However, few studies have been able to include data from historical specimens, or to compare populations/species with different bottleneck histories. In this study we examined MHC class II B and microsatellite diversity in four New Zealand passerine (songbird) species that experienced moderate to very severe declines. We compared diversity from historical samples (collected circa 1884-1938) to present day populations. Using a Bayesian framework, we found that the change in genetic diversity from historical to contemporary samples was affected by three main factors: 1) whether the data were based on MHC or microsatellite markers, 2) species (as a surrogate for bottleneck severity) and 3) whether the comparison between historical and contemporary samples was made using historical samples originating from the mainland or using historical samples originating from islands. The greatest losses in genetic diversity occurred for the most severely bottlenecked species, particularly between historical mainland and contemporary samples. Additionally, where loss of diversity occurred, the change was greater for MHC genes compared to microsatellite loci. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25488544 [PubMed - as supplied by publisher]
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9. Zoo Biol. 2014 Dec 8. doi: 10.1002/zoo.21191. [Epub ahead of print]

Ascaris spp. and Capillaria caudinflata infections in captive-bred crested ibis (Nipponia nippon) in China.

Zhang X1, Qiao JY, Wu XM, Ma QY, Hu H , Wang J, Che LF.
Author information:
1Department of Immunology and Pathogenic Biology, Medical College of Xi'an Jiaotong University, Xi'an, People's Republic of China.

Abstract

Crested ibis (Nipponia nippon), an endan gered native bird, was called the "precious stone" of oriental birds. N. nippon was considered a critically endangered species in the IUCN Red List of Threatened Species and a first-class national protected animal in China. The Chinese government had exerted considerable effort to protect the N. nippon population. An effective approach to increase the number of these birds was captive breeding. However, several pathogens, including parasites, could jeopardize the health of this species. The present study used the fecal flotation method to determine prevalence of intestinal parasites in fresh stool samples by wet mount smearing and iodine staining. Samples were obtained from 63 randomly selected crested ibis bred in Shaanxi Rare Wildlife Rescuing and Breeding Research Center in Zhouzhi County, Xi'an City, Shaanxi Province, China. In the 63 captive individuals, 38 were found positive for intestinal parasites (60.3%, 38/63). Of positive birds, high prevalence of Ascaris spp. (84.2%, 32/38) and Capillaria caudinflata (50.0%, 19/38) were detected. Coccidea (7.8%, 3/38), Fasciolidae (23.7%, 9/38), Blastocystis spp. (15.8%, 6/38), and Entamoeba histolytica (7.8%, 3/38) showed relatively low prevalence rates. This study focuses on the morphological identification of Ascaris spp. and C. caudinflata and their transmission in the N. nippon population. We introduce strategies to improve the breeding management of the birds, enhance their health, and stimulate population productivity. Zoo Biol. XX:XX-XX, 2014. © 2014 Wiley Periodicals, Inc.
© 2014 Wiley Periodicals, Inc.
PMID: 25486916 [PubMed - as supplied by publisher]
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10. Front Zool. 2014 Nov 28;11(1):85. eCollection 2014.

Behavioural response of a migratory songbird to geographic variation in song and morphology.

Mortega KG1, Flinks H2, Helm B3.
Author information:
1Department of Migration and Immuno-Ecology, Max Planck Institute for Ornithology, 78315 Radolfzell, Germany ; Department of Ornithology, University of Konstanz, 78457 Konstanz, Germany ; Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, G12 8QQ Glasgow, UK.
2Am Kuhm 19, 46325 Borken, Germany.
3Department of Ornithology, University of Konstanz, 78457 Konstanz, Germany ; Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, G12 8QQ Glasgow, UK.

Abstract

INTRODUCTION:

Sexually selected traits contribute substantially to evolutionary diversification, for example by promoting assortative mating. The contributing traits and their relevance for reproductive isolation differ between species. In birds, sexually selected acoustic and visual signals often undergo geographic divergence. Clines in these phenotypes may be used by both sexes in the context of sexual selection and territoriality. The ways conspecifics respond to geographic variation in phenotypes can give insights to possible behavioural barriers, but these may depend on migratory behaviour. We studied a migratory songbird, the Stonechat, and tested its responsiveness to geographic variation in male song and morphology. The traits are acquired differently, with possible implications for population divergence. Song can evolve quickly through cultural transmission, and thus may contribute more to the establishment of geographic variation than inherited morphological traits. We first quantified the diversity of song traits from different populations. We then tested the responses of free-living Stonechats of both sexes to male phenotype with playbacks and decoys, representing local and foreign stimuli derived from a range of distances from the local population.

RESULTS:

Both sexes discriminated consistently between stimuli from different populations, responding more strongly to acoustic and morphological traits of local than foreign stimuli. Time to approach increased, and time spent close to the stimuli and number of tail flips decreased consistently with geographic distance of the stimulus from the local population. Discriminatory response behaviour was more consistent for acoustic than for morphological traits. Song traits of the local population differed significantly from those of other populations.

CONCLUSIONS:

Evaluating an individual's perception of geographic variation in sexually selected traits is a crucial first step for understanding reproductive isolation mechanisms. We have demonstrated that in both sexes of Stonechats the responsiveness to acoustic and visual signals decreased with increasing geographic distance of stimulus origin. These findings confirm consistent, fine discrimination for both learned song and inherited morphological traits in these migratory birds. Maintenance or further divergence in phenotypic traits could lead to assortative mating, reproductive isolation, and potentially speciation.
PMCID: PMC4256809 Free PMC Article
PMID: 25484906 [PubMed - as supplied by publisher]
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11. Zoolog Sci. 2014 Dec;31(12):781-8. doi: 10.2108/zs130237.

Factors influencing phototaxis in nocturnal migrating birds.

Zhao X1, Chen M, Wu Z, Wang Z.
Author information:
1Institute of Ecology and Geobotany, Yunnan University, Kunming, Yunnan 650091, China.

Abstract

Many migratory bird species fly during the night (nocturnal migrants) and have been shown to display some phototaxis to artificial light. During 2006 to 2009, we investigated phototaxis in nocturnal migrants at Jinshan Yakou in Xinping County (N23°56', E101°30'; 2400 m above sea-level), and at the Niaowang Mountain in Funing County (N23°30', E105°35'; 1400 m above sea-level), both in the Yunnan Province of Southwest China. A total of 5069 birds, representing 129 species, were captured by mist-netting and artificial light. The extent of phototaxis effect on bird migration was examined during all four seasons, three phases of the moon, and under two weather conditions (mist and wind). Data were statistically analyzed to determine the extent to which these factors may impact phototaxis of nocturnal migrants. The results point to phototaxis in birds migrating in the spring and autumn, especially in the autumn. Furthermore, migrating birds were more readily attracted to artificial lights during nights with little moonlight, mist, and a headwind. Regardless of the initial orientation in which birds flew, either following the wind or against the wind, birds would always fly against the wind when flying towards the light. This study broadens our understanding of the nocturnal bird migration, potentially resulting in improved bird ringing practices, increased awareness, and better policies regarding bird protection.
PMID: 25483789 [PubMed - in process]
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12. N Z Vet J. 2014 Dec 6:1-12. [Epub ahead of print]

Investigation of mortalities associated with Salmonella spp. infection in wildlife on Tiritiri Matangi Island in the Hauraki Gulf of New Zealand.

van Andel M1, Jackson B, Midwinter A, Alley M, Ewen J, McInnes K, Jakob Hoff R, Reynolds A, French N.
Author information:
1 Ministry for Primary Industries , Wellington , New Zealand.

Abstract

Abstract CASE HISTORY: Salmonellosis was suspected as the cause of death in eight wild animals on Tiritiri Matangi Island, in the Hauraki Gulf of New Zealand, between November and September 2011, including three hihi (Notiomystis cincta), a tuatara (Sphenodon punctatus), a masked lapwing (Vanellus miles novaehollandiae), and a saddleback (Philesturnus carunculatus). An outbreak investigation to identify the source and distribution of infection was under taken over the summer of 2011-2012.

CLINICAL AND LABORATORY FINDINGS:

Surveillance of five species of forest bird (n=165) in December 2011 returned a single positive result for Salmonella spp. Environmental sampling of 35 key water sources and hihi supplementary feeding stations conducted in December 2011 and March 2012 returned isolates of S. enterica subspecies houtenae and S. enterica serovar Saintpaul from a stream, a dam and supplementary feeding station. The same serotypes were identified in tissue samples collected from post mortem specimens of the affected birds, and their similarity was confirmed by pulsed-field gel electrophoresis.

DIAGNOSIS:

Mortality in wildlife associated with infection with S. enterica subspecies houtenae and S. enterica serovar Saintpaul.

CLINICAL RELEVANCE:

This is the first detection of these Salmonella spp. from wild birds in New Zealand. Our study highlights how active surveillance in response to observed disease emergence (here mortalities) can provide important insight for risk assessment and management within populations of endangered species and inform risk assessment in translocation planning.
PMID: 25482376 [PubMed - as supplied by publisher]
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13. Glob Chang Biol. 2014 Dec 5. doi: 10.1111/gcb.12823. [Epub ahead of print]

Directionality of recent bird distribution shifts and climate change in Great Britain.

Gillings S1, Balmer DE, Fuller RJ.
Author information:
1British Trust for Ornithology, The Nunnery, Thetford, Norfolk, IP24 2PU, UK.

Abstract

There is good evidence that species' distributions are shifting poleward in response to climate change, and wide interest in the magnitude of such responses for scientific and conservation purposes. It has been suggested from the directions of climatic changes that species' distribution shifts may not be simply poleward, but this has been rarely tested with observed data. Here we apply a novel approach to measuring range shifts on axes ranging through 360°, to recent data on the distributions of 122 species of British breeding birds during 1988-91 and 2008-11. Although previously documented poleward range shifts have continued, with an average 13.5 km shift northward, our analysis indicates this is an underestimate because it ignores common and larger shifts that occurred along axes oriented to the northwest and northeast. Trailing edges contracted from a broad range of southerly directions. Importantly, these results are derived from systematically collected data so confounding observer-effort biases can be discounted. Analyses of climate for the same period show that whilst temperature trends should drive species along a north-northwesterly trajectory, directional responses to precipitation will depend on both the time of year that is important for determining a species' distribution, and the location of the range margin. Directions of species' range centroid shift were not correlated with spatial trends in any single climate variable. We conclude that range shifts of British birds are multi-directional, individualistic and probably determined by species-specific interactions of multiple climate factors. Climate change is predicted to lead to changes in community composition through variation in the rates that species' ranges shift; our results suggest communities could change further owing to constituent species shifting along different trajectories. We recommend more studies consider directionality in climate and range dynamics to produce more appropriate measures of observed and expected responses to climate change. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25482202 [PubMed - as supplied by publisher]
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