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Thursday, 29 January 2015

What's new for 'birdRS' in PubMed: January 2015, Week 3

birdRS PubMed Search January 2015, 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).

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

PubMed Results

1. Domest Anim Endocrinol. 2014 Dec 11;51C:96-104. doi: 10.1016/j.domaniend.2014.12.002. [Epub ahead of print]

Estradiol concentration and the expression of estrogen receptors in the testes of the domestic goose (Anser anser f. domestica) during the annual reproductive cycle.

Leska A1, Kiezun J2, Kaminska B2, Dusza L2.


Seasonal fluctuations in the activity of bird testes are regulated by a complex mechanism where androgens play a key role. Until recently, the role played by estrogens in males has been significantly underestimated. However, there is growing evidence that the proper functioning of the testes is associated with optimal estradiol (E2) concentration in both the plasma and testes of many mammalian species. Estrogens are gradually emerging as very important players in hormonal regulation of reproductive processes in male mammals. Despite the previously mentioned, it should be noted that estrogenic action is limited by the availability of specific receptors-estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Interestingly, there is a general scarcity of information concerning the estrogen responsive system in the testes of male birds, which is of particular interest in exploring the phenomenon of seasonality of reproduction. To address this question, we have investigated for the first time the simultaneous expression of testicular ERα and ERβ genes and proteins with the accompanying plasma and testicular E2 concentrations during the annual reproductive cycle of male bird. The research model was the domestic goose (Anser anser f. domestica), a species whose annual reproductive cycle can be divided into 3 distinct phases characterized by changes in testicular activity. It has been revealed that the stable plasma E2 profile did not correspond to changing intratesticular E2 profile throughout the experiment. The expression of ERα and ERβ genes and proteins was detected in gander testes and it fluctuated on a seasonal basis with lower level in breeding and sexual reactivation stages and higher level during the nonbreeding stage. Our results demonstrated changes in testicular sensitivity to estrogens in male domestic goose during the annual reproductive cycle. The seasonal pattern of estrogen receptors (ERs) expression was analyzed against the hormonal background and a potential mechanism of ERs regulation in bird testes was proposed. The present study revealed seasonal variations in the estrogen responsive system, but further research is needed to fully explore the role of estrogens in the reproductive tract of male birds.
Copyright © 2015 Elsevier Inc. All rights reserved.
PMID: 25616248 [PubMed - as supplied by publisher]

2. Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Dec;90(6-1):062302. Epub 2014 Dec 3.

Absence of red structural color in photonic glasses, bird feathers, and certain beetles.

Magkiriadou S1, Park JG2, Kim YS3, Manoharan VN4.


Colloidal glasses, bird feathers, and beetle scales can all show structural colors arising from short-ranged spatial correlations between scattering centers. Unlike the structural colors arising from Bragg diffraction in ordered materials like opals, the colors of these photonic glasses are independent of orientation, owing to their disordered, isotropic microstructures. However, there are few examples of photonic glasses with angle-independent red colors in nature, and colloidal glasses with particle sizes chosen to yield structural colors in the red show weak color saturation. Using scattering theory, we show that the absence of angle-independent red color can be explained by the tendency of individual particles to backscatter light more strongly in the blue. We discuss how the backscattering resonances of individual particles arise from cavity-like modes and how they interact with the structural resonances to prevent red. Finally, we use the model to develop design rules for colloidal glasses with red, angle-independent structural colors.
PMID: 25615088 [PubMed - as supplied by publisher]

3. Ecol Evol. 2014 Oct;4(19):3736-45. doi: 10.1002/ece3.1194. Epub 2014 Sep 8.

Species-specific differences in relative eye size are related to patterns of edge avoidance in an Amazonian rainforest bird community.

Martínez-Ortega C1, Santos ES2, Gil D1.


Eye size shows a large degree of variation among species, even after correcting for body size. In birds, relatively larger eyes have been linked to predation risk, capture of mobile prey, and nocturnal habits. Relatively larger eyes enhance visual acuity and also allow birds to forage and communicate in low-light situations. Complex habitats such as tropical rain forests provide a mosaic of diverse lighting conditions, including differences among forest strata and at different distances from the forest edge. We examined in an Amazonian forest bird community whether microhabitat occupancy (defined by edge avoidance and forest stratum) was a predictor of relative eye size. We found that relative eye size increased with edge avoidance, but did not differ according to forest stratum. Nevertheless, the relationship between edge avoidance and relative eye size showed a nonsignificant positive trend for species that inhabit lower forest strata. Our analysis shows that birds that avoid forest edges have larger eyes than those living in lighter parts. We expect that this adaptation may allow birds to increase their active daily period in dim areas of the forest. The pattern that we found raises the question of what factors may limit the evolution of large eyes.
PMID: 25614788 [PubMed]

4. Forensic Sci Int. 2014 Dec 25. pii: S0379-0738(14)00534-9. doi: 10.1016/j.forsciint.2014.12.017. [Epub ahead of print]

A Santería/Palo Mayombe ritual cauldron containing a human skull and multiple artifacts recovered in western Massachusetts, U.S.A.

Pokines JT1.


Santería and Palo Mayombe are West African-derived religions/sects with components of Catholicism, and both involve the ritual use of nonhuman skeletal remains which make them an increasing object of forensic interest. Palo Mayombe specifically involves also the use of human skeletal remains placed within ritual cauldrons or ngangas along with multiple ritual artifacts. A case of a nganga recovered from a periodically drained canal in Western Massachusetts, U.S.A. is presented. This nganga contained multiple items indicating its origin, including railroad spikes, coins, other metal objects, a stone, a glass bead, and multiple labeled and unlabeled sticks and was associated with a knife. It also contained skeletal remains of a bird and a snake as well as a nearly intact human skull of an adult male. The origin of the human remains is likely from a cemetery or as a former anatomical specimen. The find of this nganga is atypical in that it is away from the usual urban centers of Palo Mayombe in the U.S.A., and forensic practitioners should be aware that such sources of human remains may occur in their jurisdictions.
Copyright © 2015. Published by Elsevier Ireland Ltd.
PMID: 25614303 [PubMed - as supplied by publisher]

5. Chemosphere. 2015 Jan 19;126C:1-10. doi: 10.1016/j.chemosphere.2014.12.071. [Epub ahead of print]

Chlorinated, brominated and fluorinated organic pollutants in African Penguin eggs: 30 years since the previous assessment.

Bouwman H1, Govender D2, Underhill L3, Polder A4.


The African Penguin population has drastically declined over the last 100years. Changes in food availability due to over-fishing and other oceanographic changes seem to be major causes. However, it has also been 30years since organic pollutants as a potential factor have been assessed. We analysed penguin eggs collected in 2011 and 2012 from two breeding colonies 640km apart: Robben Island near Cape Town on the Atlantic Ocean coast, and Bird Island near Port Elizabeth on the Indian Ocean coast of South Africa. We quantified organochlorine pesticides, brominated flame retardants, and perfluorinated compounds (PFCs). Compared to 30years ago, concentrations of ΣDDT have remained about the same or slightly lower, while ΣPCBs declined almost four-fold. The use of DDT in malaria control is unlikely to have contributed. PFCs were detected in all eggs. Indications (non-significant) of eggshell thinning associated with ΣDDT and ΣPCB was found. It seems therefore that the concentrations of measured organic pollutants the African Penguin eggs are not contributing directly to its current demise, but concerns remain about thinner shells and desiccation. Effects of combinations of compounds and newer compounds cannot be excluded, as well as more subtle effects on reproduction, development, and behaviour.
Copyright © 2014 Elsevier Ltd. All rights reserved.
PMID: 25613517 [PubMed - as supplied by publisher]

6. Evolution. 2015 Jan 22. doi: 10.1111/evo.12607. [Epub ahead of print]

The tempo of trait divergence in GEOGRAPHIC ISOLATION: avian speciation across the Marañon Valley of Peru.

Winger BM1, Bates JM.


Geographic isolation is considered essential to most speciation events, but our understanding of what controls the pace and degree of phenotypic divergence among allopatric populations remains poor. Why do some taxa exhibit phenotypic differentiation across barriers to dispersal, whereas others do not? To test factors controlling phenotypic divergence in allopatry, we employed a comparative phylogeographic approach consisting of replicates of ecologically similar Andean bird species isolated across a major biogeographic barrier, the Marañon valley of Peru. Our study design leverages variation among co-distributed taxa in their degree of plumage, morphometric and vocal differentiation across the Marañon to examine the tempo of phenotypic evolution. We found that substantial plumage differences between populations required roughly two million years to evolve. In contrast, morphometric trait evolution showed greater idiosyncrasy and stasis. Our results demonstrate that despite a large degree of idiosyncrasy in the relationship between genetic and phenotypic divergence across taxa and environments, comparative studies within regions may reveal predictability in the pace of phenotypic divergence. Our results also suggest that social selection is important for driving differentiation of populations found in similar environments. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25611790 [PubMed - as supplied by publisher]

7. J Evol Biol. 2015 Jan 22. doi: 10.1111/jeb.12587. [Epub ahead of print]

Selection for territory acquisition is modulated by social network structure in a wild songbird.

Farine DR1, Sheldon BC.


The social environment may be a key mediator of selection that operates on animals. In many cases, individuals may experience selection not only as a function of their phenotype, but also as a function of the interaction between their phenotype and the phenotypes of the conspecifics they associate with. For example, when animals settle after dispersal, individuals may benefit from arriving early, but, in many cases, these benefits will be affected by the arrival times of other individuals in their local environment. We integrated a recently described method for calculating assortativity on weighted networks, which is the correlation between an individual's phenotype and that of its associates, into an existing framework for measuring the magnitude of social selection operating on phenotypes. We applied this approach to large-scale data on social network structure and the timing of arrival into the breeding area over three years. We found that late-arriving individuals had a reduced probability of breeding. However, the probability of breeding was also influenced by individuals' social networks. Associating with late-arriving conspecifics increased the probability of successfully acquiring a breeding territory. Hence, social selection could offset the effects of non-social selection. Given parallel theoretical developments of the importance of local network structure on population processes, and increasing data being collected on social networks in free-living populations, the integration of these concepts could yield significant insights into social evolution. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25611344 [PubMed - as supplied by publisher]

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8. J Exp Biol. 2015 Jan 15;218(Pt 2):184-93. doi: 10.1242/jeb.111187.

Bird colour vision: behavioural thresholds reveal receptor noise.

Olsson P1, Lind O2, Kelber A3.


Birds have impressive physiological adaptations for colour vision, including tetrachromacy and coloured oil droplets, yet it is not clear exactly how well birds can discriminate the reflecting object colours that they encounter in nature. With behavioural experiments, we determined colour discrimination thresholds of chickens in bright and dim light. We performed the experiments with two colour series, orange and green, covering two parts of chicken colour space. These experiments allowed us to compare behavioural results with model expectations and determine how different noise types limit colour discrimination. At intensities ranging from bright light to those corresponding to early dusk (250-10 cd m(-2)), we describe thresholds accurately by assuming a constant signal-to-noise ratio, in agreement with an invariant Weber fraction of Weber's law. Below this intensity, signal-to-noise ratio decreases and Weber's law is violated because photon-shot noise limits colour discrimination. In very dim light (below 0.05cd m(-2) for the orange series or 0.2 cd m(-2) for the green series) colour discrimination is possibly constrained by dark noise, and the lowest intensity at which chickens can discriminate colours is 0.025 and 0.08 cd m(-2) for the orange and green series, respectively. Our results suggest that chickens use spatial pooling of cone outputs to mitigate photon-shot noise. Surprisingly, we found no difference between colour discrimination of chickens and humans tested with the same test in bright light.
© 2015. Published by The Company of Biologists Ltd.
PMID: 25609782 [PubMed - in process]

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9. Poult Sci. 2015 Jan 20. pii: peu038. [Epub ahead of print]

Electroencephalographic evaluation of the effectiveness of blunt trauma to induce loss of consciousness for on-farm killing of chickens and turkeys.

Cors JC1, Gruber AD2, Günther R3, Meyer-Kühling B4, Esser KH5, Rautenschlein S6.


Euthanasia of small numbers of birds in case of injury or other illness directly on the farm may be necessary for welfare reasons. This should be done without transportation of the moribund animals in order to minimize pain and distress. Blood loss has to be avoided to minimize the risk of contaminating the environment. Cervical dislocation in combination with a blunt trauma may be an appropriate way to achieve this aim but the bird's age and body weight may influence the practicability of this method in the field. In this study, we evaluated broilers, broiler breeders, and turkeys of different age groups and weights up to nearly 16 kg for the efficacy of blunt trauma to induce unconsciousness, allowing subsequent killing of the bird without pain. The effect of blunt trauma on the brain was determined by electroencephalography (EEG). Auditory evoked potentials (AEPs) were recorded for each animal. Convulsions or tonic seizures were observed in all investigated animals after blunt trauma, including strong wing movements, torticollis, and stretching of legs. The EEG results demonstrate that the blunt trauma induced by a single, sufficiently strong hit placed in the frontoparietal region of the head led to a reduction or loss of the AEP in all groups of birds. These results clearly indicate a loss of sensibility and induction of unconsciousness, which would allow painless killing of the birds immediately after the induction of the blunt trauma.
© 2015 Poultry Science Association Inc.
PMID: 25609692 [PubMed - as supplied by publisher]

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10. J Environ Qual. 2014 Jul;43(4):1119-24. doi: 10.2134/jeq2013.09.0390.

Ammonia and nitrous oxide emissions from a commercial broiler house.

Miles DM, Moore PA, Burns RT, Brooks JP.


Complex variation in gas emissions from animal facilities has been shown in recent research reports. Uncertainties in these emission estimates are driving research activities concerning different animal species across the globe. Greenhouse gas (NO and CO) and NH concentrations were measured in a modern, tunnel-ventilated, commercial broiler house in Mississippi during five flocks (spanning approximately 1 yr). These were flocks 9 through 13 on reused pine shavings litter, representing litter reuse beyond 2 yr. Gas concentrations obtained from a photoacoustic multigas analyzer were coupled with ventilation measurements of air flow through the house to develop NH and NO emission rates. Ammonia emission during a flock (43 d) averaged approximately 14.8 ± 9.8 kg d in the commercial house (equivalent to 23.5 g bird marketed or 0.54 g bird d). Nitrous oxide emission averaged 2.3 ± 1.7 kg d in the house (equivalent to 3.64 g bird marketed or 0.085 g bird d). Emission rates increased with time from Day 1 to Day 43 and reached average values on Day 23 and 24 for NH and NO. Even with extended litter reuse, estimates of NH emissions from the broiler house agree well with recently published research that reused litter in eight or fewer flocks. This is important information for farmers who may not be able to afford to replace the litter with fresh bedding material annually.
Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
PMID: 25603060 [PubMed - in process]

11. Int J Biometeorol. 2015 Jan 20. [Epub ahead of print]

Influence of atmospheric properties on detection of wood-warbler nocturnal flight calls.

Horton KG1, Stepanian PM, Wainwright CE, Tegeler AK.


Avian migration monitoring can take on many forms; however, monitoring active nocturnal migration of land birds is limited to a few techniques. Avian nocturnal flight calls are currently the only method for describing migrant composition at the species level. However, as this method develops, more information is needed to understand the sources of variation in call detection. Additionally, few studies examine how detection probabilities differ under varying atmospheric conditions. We use nocturnal flight call recordings from captive individuals to explore the dependence of flight call detection on atmospheric temperature and humidity. Height or distance from origin had the largest influence on call detection, while temperature and humidity also influenced detectability at higher altitudes. Because flight call detection varies with both atmospheric conditions and flight height, improved monitoring across time and space will require correction for these factors to generate standardized metrics of songbird migration.
PMID: 25601781 [PubMed - as supplied by publisher]

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12. Behav Brain Res. 2015 Jan 16. pii: S0166-4328(15)00021-2. doi: 10.1016/j.bbr.2015.01.017. [Epub ahead of print]

Neural FoxP2 and FoxP1 expression in the budgerigar, an avian species with adult vocal learning.

Hara E1, Perez JM2, Whitney O2, Chen Q3, White SA4, Wright TF2.


Vocal learning underlies acquisition of both language in humans and vocal signals in some avian taxa. These bird groups and humans exhibit convergent developmental phases and associated brain pathways for vocal communication. The transcription factor FoxP2 plays critical roles in vocal learning in humans and songbirds. Another member of the forkhead box gene family, FoxP1 also shows high expression in brain areas involved in vocal learning and production. Here, we investigate FoxP2 and FoxP1 mRNA and protein in adult male budgerigars (Melopsittacus undulatus), a parrot species that exhibits vocal learning as both juveniles and adults. To examine these molecules in adult vocal learners, we compared their expression patterns in the budgerigar striatal nucleus involved in vocal learning, magnocellular nucleus of the medial striatum (MMSt), across birds with different vocal states, such as vocalizing to a female (directed), vocalizing alone (undirected), and non-vocalizing. We found that both FoxP2 mRNA and protein expressions were consistently lower in MMSt than in the adjacent striatum regardless of the vocal states, whereas previous work has shown that songbirds exhibit down-regulation in the homologous region, Area X, only after singing alone. In contrast, FoxP1 levels were high in MMSt compared to the adjacent striatum in all groups. Taken together these results strengthen the general hypothesis that FoxP2 and FoxP1 have specialized expression in vocal nuclei across a range of taxa, and suggest that the adult vocal plasticity seen in budgerigars may be a product of persistent down-regulation of FoxP2 in MMSt.
Copyright © 2015. Published by Elsevier B.V.
PMID: 25601574 [PubMed - as supplied by publisher]

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13. Mitochondrial DNA. 2015 Jan 20:1-2. [Epub ahead of print]

Complete mitochondrial genome of the Spotted dove (Streptopelia chinensis).

Yan SQ1, Guo PC, Li YM, Qi SM, Bai CY, Zhao ZH, Sun JH.


Abstract The Spotted dove (Streptopelia chinensis) is a member of the bird family Columbidae. In this study, we report the complete mitochondrial genome of this species. The mitochondrial genome of Spotted dove is a circular molecule of 16,966 bp in size and contains 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and one control region. The total base composition is 30.1% for A, 32.1% for C, 13.9% for G, and 23.9% for T. These data will be useful for the phylogenetic and population diversity analyses of birds, especially Columbidae species.
PMID: 25600734 [PubMed - as supplied by publisher]

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14. Ecotoxicol Environ Saf. 2015 Jan 16;114C:61-66. doi: 10.1016/j.ecoenv.2015.01.010. [Epub ahead of print]

Mercury concentrations in eggshells of the Southern Ground-Hornbill (Bucorvus leadbeateri) and Wattled Crane (Bugeranus carunculatus) in South Africa.

Daso AP1, Okonkwo JO2, Jansen R2, Brandao JD2, Kotzé A3.


In this study, wild hatched eggshells were collected from the nests of threatened Wattled Crane and South Ground-Hornbill in an attempt to determine their total Hg concentrations. A total of fourteen eggshell samples from both bird species were collected from different study areas in the Mpumlanga and KwaZulu-Natal Provinces of South Africa. The eggshells were acid digested under reflux and their total Hg concentrations were determined using cold-vapour atomic absorption spectrophotometry (CV-AAS). The observed total Hg levels for the South Ground-Hornbill samples ranged from 1.31 to 8.88µgg-1 dry weight (dw), except for one outlier which had an elevated 75.0µgg-1 dw. The levels obtained for the Wattled Crane samples were relatively high and these ranged from 14.84 to 36.37µgg-1 dw. Generally, all the measured total Hg concentrations for the Wattled Crane samples exceeded the estimated total Hg levels derived for eggshell which were known to cause adverse reproductive effects in avian species from previous studies. Based on these findings, it is, therefore, possible that the exposure of these birds to elevated Hg may have contributed to their present population decline.
Copyright © 2015 Elsevier Inc. All rights reserved.
PMID: 25600716 [PubMed - as supplied by publisher]

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15. Environ Monit Assess. 2015 Feb;187(2):4218. doi: 10.1007/s10661-014-4218-3. Epub 2015 Jan 20.

Veterinary antibiotic resistance, residues, and ecological risks in environmental samples obtained from poultry farms, Egypt.

Dahshan H1, Abd-Elall AM, Megahed AM, Abd-El-Kader MA, Nabawy EE.


In Egypt, poultry production constitutes one of the main sources of pollution with veterinary antibiotics (VAs) into the environment. About 80 % of meat production in Egypt is of poultry origin, and the potential environmental risks associated with the use of VAs in these farms have not yet been properly evaluated. Thus, the main purpose of this research was to evaluate the prevalence of antibiotic-resistant enteric key bacteria and the incidence of residual antibiotics in poultry farm environmental samples and to determine whether fertilizing soils with poultry litter from farms potentially brings ecological risks. From December 2011 to September 2012, a total of 225 litter, bird dropping, and water samples were collected from 75 randomly selected boiler poultry farms. A high prevalence of Escherichia coli (n = 179; 79.5 %) in contrast to the low prevalence of Salmonella spp. (n = 7; 3.1 %) was detected. Amongst E. coli isolates, serotypes O142:K86, O125:K70, O91:K, and O119:K69 were the most common. Meanwhile, Salmonella enterica serotypes emek and enteritidis were recovered. The antibiograms using the disc diffusion method revealed significantly more common resistant and multi-resistant isolates in broiler poultry farms. Residues of tetracycline and ciprofloxacin were detected at 2.125 and 1.401 mg kg(-1) mean levels, respectively, in environmental samples contaminated with E. coli-resistant strains by HPLC. The risk evaluations highlighted that tetracycline residues in poultry litter significantly display environmental risks with a hazard quotient value above 1 (1.64). Our study implies that ineffective implementation of veterinary laws which guide and guard against incorrect VA usage may potentially bring health and environmental risks.
PMID: 25600402 [PubMed - in process]

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16. Ecotoxicology. 2015 Jan 20. [Epub ahead of print]

Toxicity reference values for chlorophacinone and their application for assessing anticoagulant rodenticide risk to raptors.

Rattner BA1, Horak KE, Lazarus RS, Schultz SL, Knowles S, Abbo BG, Volker SF.


Despite widespread use and benefit, there are growing concerns regarding hazards of second-generation anticoagulant rodenticides to non-target wildlife which may result in expanded use of first-generation compounds, including chlorophacinone (CPN). The toxicity of CPN over a 7-day exposure period was investigated in American kestrels (Falco sparverius) fed either rat tissue mechanically-amended with CPN, tissue from rats fed Rozol ® bait (biologically-incorporated CPN), or control diets (tissue from untreated rats or commercial bird of prey diet) ad libitum. Nominal CPN concentrations in the formulated diets were 0.15, 0.75 and 1.5 µg/g food wet weight, and measured concentrations averaged 94 % of target values. Kestrel food consumption was similar among groups and body weight varied by less than 6 %. Overt signs of intoxication, liver CPN residues, and changes in prothrombin time (PT), Russell's viper venom time (RVVT) and hematocrit, were generally dose-dependent. Histological evidence of hemorrhage was present at all CPN dose levels, and most frequently observed in pectoral muscle and heart. There were no apparent differences in toxicity between mechanically-amended and biologically-incorporated CPN diet formulations. Dietary-based toxicity reference values at which clotting times were prolonged in 50 % of the kestrels were 79.2 µg CPN consumed/kg body weight-day for PT and 39.1 µg/kg body weight-day for RVVT. Based upon daily food consumption of kestrels and previously reported CPN concentrations found in small mammals following field baiting trials, these toxicity reference values might be exceeded by free-ranging raptors consuming such exposed prey. Tissue-based toxicity reference values for coagulopathy in 50 % of exposed birds were 0.107 µg CPN/g liver wet weight for PT and 0.076 µg/g liver for RVVT, and are below the range of residue levels reported in raptor mortality incidents attributed to CPN exposure. Sublethal responses associated with exposure to environmentally realistic concentrations of CPN could compromise survival of free-ranging raptors, and should be considered in weighing the costs and benefits of anticoagulant rodenticide use in pest control and eradication programs.
PMID: 25600128 [PubMed - as supplied by publisher]

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17. Naturwissenschaften. 2014 Aug;101(8):653-60. doi: 10.1007/s00114-014-1204-0. Epub 2014 Jun 29.

Aggressive behavior of the male parent predicts brood sex ratio in a songbird.

Szász E1, Garamszegi LZ, Hegyi G, Szöllősi E, Markó G, Török J, Rosivall B.


Brood sex ratio is often affected by parental or environmental quality, presumably in an adaptive manner that is the sex that confers higher fitness benefits to the mother is overproduced. So far, studies on the role of parental quality have focused on parental morphology and attractiveness. However, another aspect, the partner's behavioral characteristics, may also be expected to play a role in brood sex ratio adjustment. To test this hypothesis, we investigated whether the proportion of sons in the brood is predicted by the level of territorial aggression displayed by the father, in the collared flycatcher (Ficedula albicollis). The proportion of sons in the brood was higher in early broods and increased with paternal tarsus length. When controlling for breeding date and body size, we found a higher proportion of sons in the brood of less aggressive fathers. Male nestlings are more sensitive to the rearing environment, and the behavior of courting males may often be used by females to assess their future parental activity. Therefore, adjusting brood sex ratio to the level of male aggression could be adaptive. Our results indicate that the behavior of the partner could indeed be a significant determinant in brood sex ratio adjustment, which should not be overlooked in future studies.
PMID: 24973871 [PubMed - indexed for MEDLINE]

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18. Proc Biol Sci. 2014 Jul 22;281(1787). pii: 20133313. doi: 10.1098/rspb.2013.3313. Epub 2014 Jun 11.

Demographic consequences of heavy metals and persistent organic pollutants in a vulnerable long-lived bird, the wandering albatross.

Goutte A1, Barbraud C2, Meillère A2, Carravieri A2, Bustamante P3, Labadie P4, Budzinski H4, Delord K2, Cherel Y2, Weimerskirch H2, Chastel O2.


Seabirds are top predators of the marine environment that accumulate contaminants over a long life-span. Chronic exposure to pollutants is thought to compromise survival rate and long-term reproductive outputs in these long-lived organisms, thus inducing population decline. However, the demographic consequences of contaminant exposure are largely theoretical because of the dearth of long-term datasets. This study aims to test whether adult survival rate, return to the colony and long-term breeding performance were related to blood mercury (Hg), cadmium (Cd) and persistent organic pollutants (POPs), by using a capture-mark-recapture dataset on the vulnerable wandering albatross Diomedea exulans. We did not find evidence for any effect of contaminants on adult survival probability. However, blood Hg and POPs negatively impacted long-term breeding probability, hatching and fledging probabilities. The proximate mechanisms underlying these deleterious effects are likely multifaceted, through physiological perturbations and interactions with reproductive costs. Using matrix population models, we projected a demographic decline in response to an increase in Hg or POPs concentrations. This decline in population growth rate could be exacerbated by other anthropogenic perturbations, such as climate change, disease and fishery bycatch. This study gives a new dimension to the overall picture of environmental threats to wildlife populations.
© 2014 The Author(s) Published by the Royal Society. All rights reserved.
PMCID: PMC4071534 [Available on 2015/7/22]
PMID: 24920477 [PubMed - indexed for MEDLINE]

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