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Thursday, 28 May 2015

What's new for 'birdRS' in PubMed: May 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).

PubMed Results

1. Environ Pollut. 2015 May 19;205:23-32. doi: 10.1016/j.envpol.2015.05.007. [Epub ahead of print]  

Source identification of perylene in surface sediments and waterbird eggs in the Anzali Wetland, Iran.    

Zamani M(1), Khorasani N(1), Bakhtiari AR(2), Rezaei K(3).  
Author information:  
(1)Department of Environmental Sciences, Faculty of Agricultural Sciences and Natural Resources, University of Tehran, Karaj, Alborz, Iran. 

(2)Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, PO Box 64414-356, Noor, Mazandaran, Iran. Electronic address: 

(3)Department of Food Sciences, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Alborz, Iran.  

Following the marked increase of perylene concentration in southern coast of Caspian Sea, waterbird eggs were used as biomonitoring agents. Surface sediments and eggs of five bird species were collected from colonies in Anzali Wetland in the above coast for perylene analysis. The perylene concentrations in sediment and egg samples ranged within 70.6-204.4 and 25.5-43.2 ng/g dw, respectively. Diagnostic perylene ratios showed that the perylene found in all samples was of biogenic origin, possibly developing from terrestrial materials. The combination pattern of perylene was found to be similar in all samples. Conclusively, perylene observed in the area was transmitted from sediments in breeding areas into the eggs, so the eggs are biomonitoring agents and the prevalence of oxic conditions in surface sediments limits formation of perylene, reflecting perylene formation in the catchment area. We found that perylene distribution in surface sediments follows irregular patterns, representing significant effects from local inputs. 
Copyright © 2015 Elsevier Ltd. All rights reserved.  
PMID: 26000756 [PubMed - as supplied by publisher]  

2. Brain Behav Evol. 2015 May 21. [Epub ahead of print] 

Seasonal Variation in Forebrain Region Sizes in Male Ruffed Grouse (Bonasa umbellus). 

Krilow JM(1), Iwaniuk AN. 
Author information: 
(1)Department of Neuroscience, University of Lethbridge, Lethbridge, Alta., Canada. 

The song system of songbirds has provided significant insight into the underlying mechanisms and behavioural consequences of seasonal neuroplasticity. The extent to which seasonal changes in brain region volumes occur in non-songbird species has, however, remained largely untested. Here, we tested whether brain region volumes varied with season in the ruffed grouse (Bonasa umbellus), a gallinaceous bird that produces a unique wing-beating display known as 'drumming' as its primary form of courtship behaviour. Using unbiased stereology, we measured the sizes of the cerebellum, nucleus rotundus, telencephalon, mesopallium, hippocampal formation, striatopallidal complex and arcopallium across spring males, fall males and fall females. The majority of these brain regions did not vary significantly across these three groups. The two exceptions were the striatopallidal complex and arcopallium, both of which were significantly larger in spring males that are actively drumming. These seasonal changes in volume strongly implicate the striatopallidal complex and arcopallium as key structures in the production and/or modulation of the ruffed grouse drumming display and represent the first evidence of seasonal plasticity in the telencephalon underlying a non-vocal courtship behaviour. Our findings also suggest that seasonal plasticity in the striatopallidal complex and arcopallium might be a trait that is shared across many bird species and that both structures are related to the production of multiple forms of courtship and not just learned song. 
© 2015 S. Karger AG, Basel. PMID: 25997574 [PubMed - as supplied by publisher]  

3. Am Nat. 2015 Jun;185(6):769-83. doi: 10.1086/681017. Epub 2015 Apr 1. 

Immune activation generates corticosterone-mediated terminal reproductive investment in a wild bird.

Bowers EK(1), Bowden RM, Sakaluk SK, Thompson CF. 
Author information: 
(1)Behavior, Ecology, Evolution, and Systematics Section, School of Biological Sciences, Illinois State University, Normal, Illinois 61790. 

Despite classical expectations of a trade-off between immune activity and reproduction, an emergent view suggests that individuals experiencing activation of their immune system actually increase reproductive effort and allocation to offspring as a form of terminal investment in response to reduced survival probability. However, the components and mechanisms of increased parental investment following immunostimulation are currently unknown. We hypothesize that increased glucocorticoid production following immunostimulation modulates the increase in reproductive effort that constitutes terminal investment. We activated the immune system of breeding female house wrens (Troglodytes aedon) with an immunogen and cross-fostered the eggs that they subsequently produced to separate prenatal and postnatal components of maternal investment. Cross-fostering revealed an increase in both pre- and postnatal allocation from immunostimulated females, which was confirmed by quantification of egg constituents and maternal provisioning behavior. The increase in maternal provisioning was mediated, at least in part, by increased corticosterone in these females. Offspring immune responsiveness was also enhanced through transgenerational immune priming via the egg. Thus, our results indicate that maternal immunostimulation induces transgenerational effects on offspring through both pre- and postnatal parental effects and support an important role for corticosterone in mediating parental investment. 
PMID: 25996862 [PubMed - in process]  

4. Sci Context. 2015 Jun;28(2):259-284. 

Strange Birds: Ornithology and the Advent of the Collared Dove in Post-World War II Germany. 

Lachmund J(1). 
Author information: 
(1)Maastricht University 

Argument In this paper I study the engagement of German ornithologists with the Collared Dove, a bird species of Asian origin that spread massively throughout Central Europe in the 1940s and 1950s. Never before had the spread of a single species attracted so much attention from European ornithologists. Ornithologists were not only fascinated by the exotic origin of the bird, but even more so by the unprecedented rapidity of its expansion. As it is argued in the paper, the advent of the bird created an outstanding opportunity for ornithologists to study the process of biogeographic range expansion. The paper traces how knowledge on the dove's expansion took shape in the social, discursive, and material practices of a large-scale observation campaign of German ornithologists (both amateurs and academics). The paper also argues that ornithologists' observation practices have contributed to the construction of a benevolent cultural image of the Collared Dove. This sets the case of the Collared Dove apart from many recent debates in which newly arriving species have been framed as a threat to biodiversity. The paper contributes both to a historical understanding of scientific fieldwork as well as of the role of scientific knowledge in the shaping of cultural meanings of animals. 
PMID: 25996856 [PubMed - as supplied by publisher]  

5. J Acoust Soc Am. 2015 May;137(5):2542. doi: 10.1121/1.4919329. 

Integration over song classification replicates: Song variant analysis in the hihi. 

Ranjard L(1), Withers SJ(2), Brunton DH(3), Ross HA(2), Parsons S(2). 
Author information: 
(1)Bioinformatics Institute, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand. 
(2)School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand. 
(3)The Institute of Natural and Mathematical Sciences, Massey University, Albany Campus, Private Bag 102 904, North Shore Mail Centre, Auckland 0745, New Zealand. 

Human expert analyses are commonly used in bioacoustic studies and can potentially limit the reproducibility of these results. In this paper, a machine learning method is presented to statistically classify avian vocalizations. Automated approaches were applied to isolate bird songs from long field recordings, assess song similarities, and classify songs into distinct variants. Because no positive controls were available to assess the true classification of variants, multiple replicates of automatic classification of song variants were analyzed to investigate clustering uncertainty. The automatic classifications were more similar to the expert classifications than expected by chance. Application of these methods demonstrated the presence of discrete song variants in an island population of the New Zealand hihi (Notiomystis cincta). The geographic patterns of song variation were then revealed by integrating over classification replicates. Because this automated approach considers variation in song variant classification, it reduces potential human bias and facilitates the reproducibility of the results. 
PMID: 25994687 [PubMed - in process]      

6. Proc Biol Sci. 2015 Jun 7;282(1808). pii: 20150164. doi: 10.1098/rspb.2015.0164. 

Avian responses to selective logging shaped by species traits and logging practices. 

Burivalova Z(1), Lee TM(2), Giam X(3), Şekercioğlu ÇH(4), Wilcove DS(5), Koh LP(6). 
Author information: 
(1)Department of Environmental Systems Science, ETH Zürich, CHN G 73.1, Universitätstrasse 16, Zürich 8092, Switzerland 
(2)Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ 08544-1013, USA. 
(3)Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544-1013, USA School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA 98105, USA. 
(4)Department of Biology, The University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA College of Sciences, Koç University, Rumelifeneri, Sariyer 34450, Istanbul, Turkey. 
(5)Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ 08544-1013, USA Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544-1013, USA. 
(6)Environment Institute, and School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia. 

Selective logging is one of the most common forms of forest use in the tropics. Although the effects of selective logging on biodiversity have been widely studied, there is little agreement on the relationship between life-history traits and tolerance to logging. In this study, we assessed how species traits and logging practices combine to determine species responses to selective logging, based on over 4000 observations of the responses of nearly 1000 bird species to selective logging across the tropics. Our analysis shows that species traits, such as feeding group and body mass, and logging practices, such as time since logging and logging intensity, interact to influence a species' response to logging. Frugivores and insectivores were most adversely affected by logging and declined further with increasing logging intensity. Nectarivores and granivores responded positively to selective logging for the first two decades, after which their abundances decrease below pre-logging levels. Larger species of omnivores and granivores responded more positively to selective logging than smaller species from either feeding group, whereas this effect of body size was reversed for carnivores, herbivores, frugivores and insectivores. Most importantly, species most negatively impacted by selective logging had not recovered approximately 40 years after logging cessation. We conclude that selective timber harvest has the potential to cause large and long-lasting changes in avian biodiversity. However, our results suggest that the impacts can be mitigated to a certain extent through specific forest management strategies such as lengthening the rotation cycle and implementing reduced impact logging. 
© 2015 The Author(s) Published by the Royal Society. All rights reserved. PMID: 25994673 [PubMed - in process]  

7. J Exp Biol. 2015 May 15;218(Pt 10):1464-6. doi: 10.1242/jeb.109348. 

An amazing discovery: bird navigation based on olfaction. 

Wallraff HG(1). 
Author information: 
(1)Max Planck Institute for Ornithology 
 PMID: 25994630 [PubMed - in process]  

8. PLoS One. 2015 May 20;10(5):e0124039. doi: 10.1371/journal.pone.0124039. eCollection 2015. 

Reanalysis of Wupus agilis (Early Cretaceous) of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks. 

Xing L(1), Buckley LG(2), McCrea RT(2), Lockley MG(3), Zhang J(1), Piñuela L(4), Klein H(5), Wang F(6). 
Author information: 
(1)School of the Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, China. 
(2)Peace Region Palaeontology Research Centre, Tumbler Ridge, British Columbia, Canada. 
(3)Dinosaur Tracks Museum, University of Colorado Denver, Denver, Colorado, United States of America. 
(4)Museo del Jurásico de Asturias MUJA (Jurassic Museum of Asturias), Colunga, Spain. 
(5)Saurierwelt Paläontologisches Museum, Neumarkt, Germany. 
(6)Qijiang District Bureau of Land Resources, Chongqing, China. 

Trace fossils provide the only records of Early Cretaceous birds from many parts of the world. The identification of traces from large avian track-makers is made difficult given their overall similarity in size and tridactyly in comparison with traces of small non-avian theropods. Reanalysis of Wupus agilis from the Early Cretaceous (Aptian-Albian) Jiaguan Formation, one of a small but growing number of known avian-pterosaur track assemblages, of southeast China determines that these are the traces of a large avian track-maker, analogous to extant herons. Wupus, originally identified as the trace of a small non-avian theropod track-maker, is therefore similar in both footprint and trackway characteristics to the Early Cretaceous (Albian) large avian trace Limiavipes curriei from western Canada, and Wupus is reassigned to the ichnofamily Limiavipedidae. The reanalysis of Wupus reveals that it and Limiavipes are distinct from similar traces of small to medium-sized non-avian theropods (Irenichnites, Columbosauripus, Magnoavipes) based on their relatively large footprint length to pace length ratio and higher mean footprint splay, and that Wupus shares enough characters with Limiavipes to be reassigned to the ichnofamily Limiavipedidae. The ability to discern traces of large avians from those of small non-avian theropods provides more data on the diversity of Early Cretaceous birds. This analysis reveals that, despite the current lack of body fossils, large wading birds were globally distributed in both Laurasia and Gondwana during the Early Cretaceous. 
PMID: 25993285 [PubMed - in process]  

9. PLoS Pathog. 2015 May 20;11(5):e1004874. doi: 10.1371/journal.ppat.1004874. eCollection 2015. 

Experimental evolution of an RNA virus in wild birds: evidence for host-dependent impacts on population structure and competitive fitness. 

Grubaugh ND(1), Smith DR(1), Brackney DE(1), Bosco-Lauth AM(1), Fauver JR(1), Campbell CL(1), Felix TA(2), Romo H(3), Duggal NK(4), Dietrich EA(4), Eike T(1), Beane JE(5), Bowen RA(6), Black WC(1), Brault AC(4), Ebel GD(1). 
Author information: 
(1)Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America. 
(2)United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Lakewood, Colorado, United States of America. 
(3)Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America; Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America. 
(4)Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America. 
(5)Section for Computational Biomedicine, Boston University School of Medicine, Boston, Massachusetts, United States of America. 
(6)Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America. 

Within hosts, RNA viruses form populations that are genetically and phenotypically complex. Heterogeneity in RNA virus genomes arises due to error-prone replication and is reduced by stochastic and selective mechanisms that are incompletely understood. Defining how natural selection shapes RNA virus populations is critical because it can inform treatment paradigms and enhance control efforts. We allowed West Nile virus (WNV) to replicate in wild-caught American crows, house sparrows and American robins to assess how natural selection shapes RNA virus populations in ecologically relevant hosts that differ in susceptibility to virus-induced mortality. After five sequential passages in each bird species, we examined the phenotype and population diversity of WNV through fitness competition assays and next generation sequencing. We demonstrate that fitness gains occur in a species-specific manner, with the greatest replicative fitness gains in robin-passaged WNV and the least in WNV passaged in crows. Sequencing data revealed that intrahost WNV populations were strongly influenced by purifying selection and the overall complexity of the viral populations was similar among passaged hosts. However, the selective pressures that control WNV populations seem to be bird species-dependent. Specifically, crow-passaged WNV populations contained the most unique mutations (~1.7× more than sparrows, ~3.4× more than robins) and defective genomes (~1.4× greater than sparrows, ~2.7× greater than robins), but the lowest average mutation frequency (about equal to sparrows, ~2.6× lower than robins). Therefore, our data suggest that WNV replication in the most disease-susceptible bird species is positively associated with virus mutational tolerance, likely via complementation, and negatively associated with the strength of selection. These differences in genetic composition most likely have distinct phenotypic consequences for the virus populations. Taken together, these results reveal important insights into how different hosts may contribute to the emergence of RNA viruses. 
PMID: 25993022 [PubMed - in process]  

10. PLoS One. 2015 May 20;10(5):e0124876. doi: 10.1371/journal.pone.0124876. eCollection 2015. 

The songbird as a percussionist: syntactic rules for non-vocal sound and song production in java sparrows. 

Soma M(1), Mori C(2). 
Author information: 
(1)Department of Biology, Faculty of Science, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan. 
(2)Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan. 

Music and dance are two remarkable human characteristics that are closely related. Communication through integrated vocal and motional signals is also common in the courtship displays of birds. The contribution of songbird studies to our understanding of vocal learning has already shed some light on the cognitive underpinnings of musical ability. Moreover, recent pioneering research has begun to show how animals can synchronize their behaviors with external stimuli, like metronome beats. However, few studies have applied such perspectives to unraveling how animals can integrate multimodal communicative signals that have natural functions. Additionally, studies have rarely asked how well these behaviors are learned. With this in mind, here we cast a spotlight on an unusual animal behavior: non-vocal sound production associated with singing in the Java sparrow (Lonchura oryzivora), a songbird. We show that male Java sparrows coordinate their bill-click sounds with the syntax of their song-note sequences, similar to percussionists. Analysis showed that they produced clicks frequently toward the beginning of songs and before/after specific song notes. We also show that bill-clicking patterns are similar between social fathers and their sons, suggesting that these behaviors might be learned from models or linked to learning-based vocalizations. Individuals untutored by conspecifics also exhibited stereotypical bill-clicking patterns in relation to song-note sequence, indicating that while the production of bill clicking itself is intrinsic, its syncopation appears to develop with songs. This paints an intriguing picture in which non-vocal sounds are integrated with vocal courtship signals in a songbird, a model that we expect will contribute to the further understanding of multimodal communication. 
PMID: 25992841 [PubMed - in process]  

11. PLoS One. 2015 May 20;10(5):e0122617. doi: 10.1371/journal.pone.0122617. eCollection 2015. 

The long term response of birds to climate change: new results from a cold stage avifauna in northern England. 

Stewart JR(1), Jacobi RM(2). 
Author information: 
(1)Faculty of Science and Technology, Bournemouth University, Talbot Campus, Fern Barrow, Poole, Dorset, BH12 5BB, United Kingdom. 
(2)Department of Earth Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom. 

The early MIS 3 (55-40 Kyr BP associated with Middle Palaeolithic archaeology) bird remains from Pin Hole, Creswell Crags, Derbyshire, England are analysed in the context of the new dating of the site's stratigraphy. The analysis is restricted to the material from the early MIS 3 level of the cave because the upper fauna is now known to include Holocene material as well as that from the Late Glacial. The results of the analysis confirm the presence of the taxa, possibly unexpected for a Late Pleistocene glacial deposit including records such as Alpine swift, demoiselle crane and long-legged buzzard with southern and/or eastern distributions today. These taxa are accompanied by more expected ones such as willow ptarmigan /red grouse and rock ptarmigan living today in northern and montane areas. Finally, there are temperate taxa normally requiring trees for nesting such as wood pigeon and grey heron. Therefore, the result of the analysis is that the avifauna of early MIS 3 in England included taxa whose ranges today do not overlap making it a non-analogue community similar to the many steppe-tundra mammalian faunas of the time. The inclusion of more temperate and woodland taxa is discussed in the light that parts of northern Europe may have acted as cryptic northern refugia for some such taxa during the last glacial. These records showing former ranges of taxa are considered in the light of modern phylogeographic studies as these often assume former ranges without considering the fossil record of those taxa. In addition to the anomalous combination of taxa during MIS 3 living in Derbyshire, the individuals of a number of the taxa are different in size and shape to members of the species today probably due to the high carrying capacity of the steppe-tundra. 
PMID: 25992609 [PubMed - in process]      

12. PLoS One. 2015 May 18;10(5):e0127692. doi: 10.1371/journal.pone.0127692. eCollection 2015. 

Revealing Beta-diversity patterns of breeding bird and lizard communities on inundated land-bridge islands by separating the turnover and nestedness components. 

Si X(1), Baselga A(2), Ding P(1). 
Author information: 
(1)College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China. 
(2)Departamento de Zoología, Facultad de Biología, Universidad de Santiago de Compostela, c/Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain. 

Beta diversity describes changes in species composition among sites in a region and has particular relevance for explaining ecological patterns in fragmented habitats. However, it is difficult to reveal the mechanisms if broad sense beta-diversity indices (i.e. yielding identical values under nestedness and species replacement) are used. Partitioning beta diversity into turnover (caused by species replacement from site to site) and nestedness-resultant components (caused by nested species losses) could provide a unique way to understand the variation of species composition in fragmented habitats. Here, we collected occupancy data of breeding birds and lizards on land-bridge islands in an inundated lake in eastern China. We decomposed beta diversity of breeding bird and lizard communities into spatial turnover and nestedness-resultant components to assess their relative contributions and respective relationships to differences in island area, isolation, and habitat richness. Our results showed that spatial turnover contributed more to beta diversity than the nestedness-resultant component. The degree of isolation had no significant effect on overall beta diversity or its components, neither for breeding birds nor for lizards. In turn, in both groups the nestedness-resultant component increased with larger differences in island area and habitat richness, respectively, while turnover component decreased with them. The major difference among birds and lizards was a higher relevance of nestedness-resultant dissimilarity in lizards, suggesting that they are more prone to local extinctions derived from habitat fragmentation. The dominance of the spatial turnover component of beta diversity suggests that all islands have potential conservation value for breeding bird and lizard communities. 
PMID: 25992559 [PubMed - in process]  

13. Mitochondrial DNA. 2015 May 20:1-3. [Epub ahead of print] 

Complete mitochondrial genome of a sunbird, Aethopyga gouldiae (Aves: Passeriformes), the first representative of Nectariniidae. 

Wang N(1), Liang B. 
Author information: 
(1)Ministry of Education Key Laboratory for Tropical Plant and Animal Ecology, College of Life Sciences, Hainan Normal University , Haikou , China. 

The first complete mitochondrial genome of a sunbird was determined for Gould's sunbird Aethopyga gouldiae. The identity of the sample was verified by conducting nucleotide blast for each mitochondrial ribosomal RNA and protein-coding gene, and by estimating its phylogenetic position using five genes (12S, ND2, ATP6, ND3, CYTb) and 52 passerines (including 17 sunbirds and allies). The mitogenomic length of A. gouldiae was 16,893 bp, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. The nucleotide composition of the genome shows a bias toward A + T. Since the sunbirds and allies form a large bird group that feeds on nectar, along with the hummingbirds and honeyeaters, the mitogenome of A. gouldiae could contribute to understand the evolution of feeding behavior in birds and the phylogenetic position of the sunbirds. 
PMID: 25990041 [PubMed - as supplied by publisher]  

14. Virol J. 2015 May 20;12(1):80. [Epub ahead of print] 

Evolutionary relationships of West Nile virus detected in mosquitoes from a migratory bird zone of Colombian Caribbean. 

López RH(1,)(2), Soto SU(3), Gallego-Gómez JC(4). 
Author information: 
(1)Molecular and Translational Medicine Group, Medical Research Institute, Faculty of Medicina, Universidad de Antioquia, Medellín, Colombia. 
(2)Molecular Systematics Research Group, Biosciences School - Sciences Faculty, Universidad Nacional de Colombia, Medellín, Colombia. 
(3)Molecular Systematics Research Group, Biosciences School - Sciences Faculty, Universidad Nacional de Colombia, Medellín, Colombia. 
(4)Molecular and Translational Medicine Group, Medical Research Institute, Faculty of Medicina, Universidad de Antioquia, Medellín, Colombia. 

BACKGROUND: West Nile virus (WNV) is a member of the genus Flavivirus, and it is transmitted between Culex sp. mosquitoes and avian hosts. Equids and humans are commonly infected with WNV as dead-end hosts, and the signs and symptoms of infection range from mild illness to neurologic symptoms as encephalitis, meningitis and sometimes death. Previous phylogenetic studies have classified WNV into six genetically distinct lineages and provided valuable insight on WNV dispersal patterns within the Americas and its emergence in different geographic areas. In this study, we isolated, sequenced and genetically characterized the NS5 and envelope genes for two WNV strains detected from Northern of Colombia. Herein we describe the evolutionary relationships with representative WNV-strains isolated in a variety of epidemic outbreaks and countries, to define the phylogeographic origin and possible implications in the epidemiology of this emergent virus in Colombia. 
FINDINGS: Fragments of the NS5 and Envelope genes were amplified with RT-PCR and sequenced to obtain 1186-nt and 1504-nt portions, respectively. Our sequences were aligned with 46 sequences from WNV-strains collected in the U.S., Mexico and Argentina for phylogenetic reconstruction using Bayesian methods. Sequence analyses identified unique non-synonymous substitutions in the envelope gene of the WNV strains we detected, and our sequences clustered together with those from the attenuated Texas - 2002 genotype. 
CONCLUSIONS: A new strain closely related to attenuated strains collected in Texas during 2002 was identified from Colombia by phylogenetic analysis. This finding may explain the absence of human/equine cases of WNV-encephalitis or severe disease in Colombia and possibly other regions of South America. Follow-up studies are needed in ecosystems used by migratory birds areas and virological/entomological surveillance. 
PMID: 25989901 [PubMed - as supplied by publisher]  

15. Environ Toxicol Chem. 2015 May 18. doi: 10.1002/etc.2992. [Epub ahead of print] 

Temporal trends of perfluoroalkyl substances (PFAS) in eggs of coastal and offshore birds: Increasing PFAS levels associated with offshore bird species breeding on the Pacific coast of Canada and wintering near Asia. 

Miller A(1), Elliott JE(1,)(2), Elliott KH(3), Lee S(2), Cyr F(4). 
Author information: 
(1)Department of Applied Biology, University of British Columbia, Vancouver, British Columbia, Canada. 
(2)Science and Technology Branch, Pacific Wildlife Research Centre, Environment Canada, Delta, British Columbia, Canada. 
(3)Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada. 
(4)Environment Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada. 

Perfluoroalkyl substances (PFAS) such as perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs) have become virtually ubiquitous throughout the environment, and, based on laboratory studies, have known toxicological consequences. Various national and international voluntary phase-outs and restrictions on these compounds have been implemented over the last 10 to 15 years. In the present study, we examine trends (1990/1991-2010/2011) in aquatic birds (ancient murrelet, Synthliboramphus antiquus [2009 only]; Leach's storm-petrels, Oceanodroma leucorhoa; rhinoceros auklets, Cerorhinca monocerata; double-crested cormorants, Phalacrocorax auritus; and great blue herons, Ardea herodias). The PFCA, PFSA, and stable isotope (δ(15) N and δ(13) C) data collected from these species from the Pacific coast of Canada, ranging over 20 to 30 years, were used to investigate temporal changes in PFAS coupled to dietary changes. Perfluorooctane sulfonic acid (PFOS), the dominant PFSA compound in all 4 species, increased and subsequently decreased in auklet and cormorant eggs in line with the manufacturing phase-out of PFOS and perfluorooctanoic acid (PFOA), but concentrations continuously increased in petrel eggs and remained largely unchanged in heron eggs. Dominant PFCA compounds varied between the offshore and coastal species, with increases seen in the offshore species and little or variable changes seen in the coastal species. Little temporal change was seen in stable isotope values, indicating that diet alone is not driving observed PFAS concentrations. 
Environ Toxicol Chem 2015;9999:1-10. © 2015 SETAC. © 2015 SETAC. PMID: 25989421 [PubMed - as supplied by publisher]  

16. Gen Comp Endocrinol. 2015 May 16. pii: S0016-6480(15)00135-5. doi: 10.1016/j.ygcen.2015.05.005. [Epub ahead of print] 

Advanced seasonal reproductive development in a male urban bird is reflected in earlier plasma luteinizing hormone rise but not energetic status. 
Davies S(1), Behbahaninia H(2), Giraudeau M(3), Meddle SL(4), Waites K(2), Deviche P(2). 
 Author information: 
(1)School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA; Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA(1). Electronic address: 
(2)School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA. 
(3)School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA; School of Biological Sciences, University of Sydney, Heydon-Laurence Bldg AO8, Science Rd., Sydney, NSW 2006, Australia(1). 
(4)The Roslin Institute, The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Midlothian EH25 9RG, Scotland, UK. 

Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees. 
Copyright © 2015. Published by Elsevier Inc. PMID: 25985895 [PubMed - as supplied by publisher]  

17. Sci Rep. 2015 May 18;5:10239. doi: 10.1038/srep10239. 

Assessment of predation risk through referential communication in incubating birds. 

Suzuki TN(1). 
Author information: 
(1)Department of Evolutionary Studies of Biosystems, The Graduate University for Advanced Studies, Kanagawa, Japan. 

Parents of many bird species produce alarm calls when they approach and deter a nest predator in order to defend their offspring. Alarm calls have been shown to warn nestlings about predatory threats, but parents also face a similar risk of predation when incubating eggs in their nests. Here, I show that incubating female Japanese great tits, Parus minor, assess predation risk by conspecific alarm calls given outside the nest cavity. Tits produce acoustically discrete alarm calls for different nest predators: "jar" calls for snakes and "chicka" calls for other predators such as crows and martens. Playback experiments revealed that incubating females responded to "jar" calls by leaving their nest, whereas they responded to "chicka" calls by looking out of the nest entrance. Since snakes invade the nest cavity, escaping from the nest helps females avoid snake predation. In contrast, "chicka" calls are used for a variety of predator types, and therefore, looking out of the nest entrance helps females gather information about the type and location of approaching predators. These results show that incubating females derive information about predator type from different types of alarm calls, providing a novel example of functionally referential communication. 
PMID: 25985093 [PubMed - in process]  

18. J Comp Psychol. 2015 May;129(2):89-120. doi: 10.1037/a0038746. 

The string-pulling paradigm in comparative psychology. 

Jacobs IF(1), Osvath M(1). 
Author information: 
(1)Lund University. 

String pulling is one of the most widely used paradigms in comparative psychology. First documented 2 millennia ago, it has been a well-established scientific paradigm for a century. More than 160 bird and mammal species have been tested in over 200 studies with countless methodological variations. The paradigm can be used to address a wide variety of issues on animal cognition; for example, what animals understand about contact and connection as well as whether they rely on perceptual feedback, grasp the functionality of strings, generalize across conditions, apply their knowledge flexibly, and possess insight. Mammals are typically tested on a horizontal configuration, birds on a vertical one, making the studies difficult to compare; in particular, pulling a string vertically requires better coordination and attention. A species' performance on the paradigm is often influenced by its ecology, especially concerning whether limbs are used for foraging. Many other factors can be of importance and should be considered. The string-pulling paradigm is easy to administer, vary, and apply to investigate a wide array of cognitive abilities. Although it can be and has been used to compare species, divergent methods and unclear reporting have limited its comparative utility. With increasing research standards, the paradigm is expected to become an even more fundamental tool in comparative psychology. 
(PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID: 25984937 [PubMed - in process]  

19. Sci Total Environ. 2015 May 14;527-528C:448-454. doi: 10.1016/j.scitotenv.2015.05.018. [Epub ahead of print] 

Mercury in wintering seabirds, an aggravating factor to winter wrecks? 

Fort J(1), Lacoue-Labarthe T(2), Nguyen HL(3), Boué A(4), Spitz J(5), Bustamante P(6). 
Author information: 
(1)Littoral, Environnement et Sociétés, UMRi 7266 CNRS - Université La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle, France. Electronic address: 
(2)Littoral, Environnement et Sociétés, UMRi 7266 CNRS - Université La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle, France. Electronic address: 
(3)Littoral, Environnement et Sociétés, UMRi 7266 CNRS - Université La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle, France; University of Science and Technology of Hanoi, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Viet Nam. Electronic address: 
(4)LPO (Ligue pour la Protection des Oiseaux), Fonderies Royales, 8 rue du Dr Pujos, 17305 Rochefort, France. Electronic address: 
(5)Observatoire PELAGIS, UMS 3462 CNRS - Université La Rochelle, La Rochelle, France. Electronic address: 
(6)Littoral, Environnement et Sociétés, UMRi 7266 CNRS - Université La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle, France. Electronic address: 

Every year, thousands of seabirds are cast ashore and are found dead along the coasts of North America and Western Europe. These massive mortality events called 'winter wrecks' have generally been attributed to harsh climatic conditions and prolonged storms which affect bird energy balance and impact their body condition. Nevertheless, additional stress factors, such as contaminant body burden, could potentially cumulate to energy constraints and actively contribute to winter wrecks. However, the role played by these additional factors in seabird massive winter mortality has received little attention to date. In February/March 2014, an unprecedented seabird wreck occurred along the Atlantic French coasts during which >43,000 seabirds were found dead. By analyzing mercury (Hg) concentrations in various tissues collected on stranded birds, we tested the hypothesis that Hg played a significant role in this mortality. More specifically, we aimed to (1) describe Hg contamination in wintering seabirds found along the French coasts in 2014, and (2) determine if Hg concentrations measured in some vital organs such as kidney and brain reached toxicity thresholds that could have led to deleterious effects and to an enhanced mortality. We found some of the highest Hg levels ever reported in Atlantic puffins, common guillemots, razorbills and kittiwakes. Measured concentrations ranged from 0.8 to 3.6μg·g(-1) of dry weight in brain, 1.3 to 7.2μg·g(-1) in muscle, 2.5 to 13.5μg·g(-1) in kidney, 2.9 to 18.6μg·g(-1) in blood and from 3.1 to 19.5μg·g(-1) in liver. Hg concentrations in liver and brain were generally below the estimated acute toxicity levels. However, kidney concentrations were not different than those measured in the liver, and above levels associated to renal sub-lethal effects, suggesting a potential Hg poisoning. We concluded that although Hg was not directly responsible for the high observed mortality, it has been a major aggravating stress factor for emaciated birds already on the edge. Importantly, this study also demonstrated that total blood, which can be non-lethally collected in seabirds, can be used as a predictor of Hg contamination in other tissues. 
 Copyright © 2015 Elsevier B.V. All rights reserved. 
 PMID: 25984703 [PubMed - as supplied by publisher]  

20. J Biol Res (Thessalon). 2014 Jul 1;21(1):12. doi: 10.1186/2241-5793-21-12. eCollection 2014. 

Movements of a juvenile Crowned Eagle (Harpyhaliaetus coronatus) tracked by satellite telemetry in central Argentina.  

Urios V(1), Donat-Torres MP(2), Bechard M(3), Ferrer M(4).  
Author information:  
(1)Estación Biológica Terra Natura, Universidad de Alicante, Alicante, E-03080 Spain. 
(2)Instituto de Investigación para la Gestión Integrada de Zonas Costeras IGIC, Universidad Politecnica de Valencia, Gandia, E-46730 Spain. 
(3)Department of Biology, Boise State University, Boise, ID 83725-1515 USA. 
(4)Departamento de Etología y Conservación de la Biodiversidad, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas CSIC, Sevilla, E-41092 Spain.  

BACKGROUND: A juvenile Crowned Eagle was tagged at its nest with a satellite transmitter. The Crowned Eagle (Harpyhaliaetus coronatus) is one of the most unknown raptor species from the American continent. Their current distribution ranges from central Brazil to central Argentina, with a total population of 350-1500 individuals across this large area, being thus largely fragmented.  
RESULTS: During the three years of tracking the bird concentrated its movements in a range spanning for 12845 km(2), but concentrating mainly in four smaller areas accounting for 3073 km(2). The locations were recorded mainly over shrubland habitats (86.5%), whereas other habitats used were different types of mosaics that included cropland and natural vegetation (forest, shrubland or grassland) close to wetlands.  
CONCLUSIONS: The home-range estimated for this individual during the whole period was 12845 km(2) (according to 95% fixed kernel). However, the bird concentrated most of its movements in smaller areas (as defined above), that accounted for a total of 3073 km(2) (50% fixed kernel). During these three years, most of the locations of the juvenile solitary Crowned Eagle were recorded over shrubland habitats (86.5% of the locations). Understanding in a more detailed way the juvenile ranging behaviour and habitat preferences would be of great importance for the conservation of the Crowned Eagle.  
PMCID: PMC4389320 PMID: 25984495 [PubMed]

The Condor: May 2015 : Volume 117 Issue 2, Abstracts

The Condor
Published by: Cooper Ornithological Society

Table of Contents
May 2015 : Volume 117 Issue 2, LINK 


The relative importance of multiscale factors in the distribution of Bachman's Sparrow and the implications for ecosystem conservation
Paul J. Taillie, M. Nils Peterson, and Christopher E. Moorman

Recent research has shown that landscape-level changes, namely habitat loss and fragmentation, can play an important role in determining the distribution of species across a variety of ecological systems. However, the influence of these large-scale factors in relation to small-scale factors, such as local vegetation structure or composition, is poorly understood. We used Bachman's Sparrow (Peucaea aestivalis) as a surrogate species to measure the relative importance of local vegetation and large-scale habitat distribution in the Onslow Bight region of North Carolina, USA. We conducted repeated point counts at 232 points within 111 habitat patches between April 10 and July 20, 2011. We then fit a series of single-season occupancy models, including both local and landscape-level predictors, to identify those that best explained the distribution of Bachman's Sparrows. We documented a strong response to vegetation characteristics best maintained via prescribed fire, but the most influential predictor of Bachman's Sparrow occupancy was the amount of habitat within 3 km. Specifically, the probability of Bachman's Sparrow occurrence was close to zero in landscapes comprised of <10% habitat, regardless of local vegetation conditions. Our results illustrate the strong influence of habitat loss on Bachman's Sparrow and likely on other members of this community, many of which are of high conservation concern.

Modeling the demography and population dynamics of a subtropical seabird, and the influence of environmental factors
Susan M. Waugh, Christophe Barbraud, Lynn Adams, Amanda N. D. Freeman, Kerry-Jayne Wilson, Graham Wood, Todd J. Landers, and G. Barry Baker

The use of long-term ecological datasets to explore the importance of the effects of environmental variability on higher predator populations has been focused mainly on high-latitude areas. We modeled the population dynamics of the Westland Petrel (Procellaria westlandica), which spends its time mostly in subtropical waters during both breeding and the interbreeding migration across the Pacific Ocean. We found that the population has slowly increased since the early 1970s, a result of high adult survival, high fecundity (0.6 of all eggs laid survived to fledge) and moderate mean age at first return to the colony (7.7 yr; a recruitment age typical for this genus), strong recruitment rate of juveniles, and negligible emigration. The modeled population trends were supported by similar rates of increase in nest occupancy since 2001 and nest density since 2007. Annual adult survival for breeders was the same for both sexes (0.954, 95% CI: 0.918–0.975) and constant across years. However, nonbreeders had lower survival rates than breeders, and, among nonbreeders, males tended to survive better (0.926, 95% CI: 0.917–0.934) than females (0.917, 95% CI: 0.900–0.931). Breeders transitioned to the nonbreeding state at a rate of 0.232 and nonbreeders to the breeding state at a rate of 0.295. Sea-surface temperature anomalies had a negative effect on adult survival during the breeding period and a positive effect on survival outside the breeding season. Local marine productivity as measured by fishery catches was strongly correlated with adult survival: Years with a greater fish catch were also years of higher adult survival. Despite many threats operating throughout the breeding and foraging range of Westland Petrels, it appears that marine environmental change is a strongly influential factor for the species, with uncertainty in population growth due to predicted increases in sea-surface temperature in the future.

Cowbird responses to aircraft with lights tuned to their eyes: Implications for bird–aircraft collisions
Megan S. Doppler, Bradley F. Blackwell, Travis L. DeVault, and Esteban Fernández-Juricic

Collisions between birds and aircraft (bird strikes) are expensive, risk human lives, and increase bird mortality. Aircraft lighting has been proposed as a potential means of enhancing avian responses to aircraft. Determining the optimal changes to lighting to reduce bird strikes is a complicated problem because avian visual systems differ markedly from that of humans. Icteridae, including Brown-headed Cowbirds (Molothrus ater; hereafter “cowbirds”), are involved in bird strikes, have a well-described visual system, and respond to approaching vehicles and lights. Our goal was to assess cowbirds' responses to a remote-controlled (RC) aircraft fitted with lights tuned to the cowbird eye. On the basis of perceptual modeling (i.e. visual physiology, object and background reflectance, and ambient light conditions), we found that 470-nm lights (“blue” portion of the human spectrum) would be the most conspicuous wavelength for cowbirds. We used field experiments to examine cowbird response to 470-nm light treatments. Cowbirds exhibited alert behaviors to a stationary RC aircraft with lights on (both continuous and pulsing) in less than half the time they took to do so with lights off. In response to an approaching RC aircraft, cowbird alert responses were delayed at higher aircraft speeds with the lights off, and we noted a less pronounced speed effect with pulsing lights. However, this interaction effect of aircraft speed and lighting was eliminated with continuous lights. Additionally, higher ambient noise levels delayed cowbirds' avoidance responses to the RC aircraft, possibly influencing cowbird behavior as a sensory distractor. We suggest that some types of lighting may enhance the birds' detection and visual tracking of aircraft at high speeds and, thus, holds some potential as a means of reducing the frequency of bird strikes. This sensory-based approach also has implications for management of other bird–object collision problems.

Apparent foraging success reflects habitat quality in an irruptive species, the Black-backed Woodpecker
Christopher T. Rota, Mark A. Rumble, Chad P. Lehman, Dylan C. Kesler, and Joshua J. Millspaugh

Dramatic fluctuations in food resources are a key feature of many habitats, and many species have evolved a movement strategy to exploit food resources that are unpredictable in space and time. The availability of food resources may be a particularly strong determinant of habitat quality for irruptive bird species. We studied the apparent foraging success of Black-backed Woodpeckers (Picoides arcticus), an irruptive species that responds opportunistically to pulsed food resources in burned forests and mountain pine beetle (MPB) infestations. Prior investigations revealed that the highest population growth rates of Black-backed Woodpeckers occurred in habitat created by summer wildfire, with intermediate population growth rates in MPB infestations, and the lowest population growth rates in habitats created by prescribed fire in fall. We tested whether apparent foraging success was associated with known habitat quality in order to assess the potential for food availability to regulate population growth. We counted the number of successfully captured wood-boring beetle larvae and “small” prey on each tree that a Black-backed Woodpecker used for foraging and modeled these counts as a function of habitat, tree diameter, number of years postfire, and tree disturbance category. Total apparent foraging success (the sum of observed captures of wood-boring beetle larvae and small prey per tree) did not vary across habitats, but woodpeckers foraging in habitats created by summer wildfire were expected to capture 2.2 and 2.0 times more wood-boring beetles than woodpeckers foraging in habitats created by fall prescribed fire and MPB infestations, respectively. These results suggest that the availability of food resources may contribute to population regulation in this irruptive species. Furthermore, population growth in irruptive species may be highly sensitive to the availability of preferred food resources. Forests recently burned by summer wildfires provide relatively abundant food resources for Black-backed Woodpeckers and represent high-quality habitat for this species of conservation concern.

Urban residents' perceptions of birds in the neighborhood: Biodiversity, cultural ecosystem services, and disservices 
J. Amy Belaire, Lynne M. Westphal, Christopher J. Whelan, and Emily S. Minor

As our world becomes increasingly urbanized, cities are often where we come into contact with the natural world—not just in parks and urban nature preserves, but in more familiar places like residential yards. We conducted bird surveys and social surveys in Chicago-area residential landscapes near forest preserves (primarily in middle- and high-income areas) to examine residents' perceptions of the birds that co-inhabit their neighborhoods and the relationship of those perceptions with characteristics of the bird community. We found that residents value many aspects of neighborhood birds, especially those related to aesthetics and birds' place in the ecosystem. Our results indicate that while birds were generally well liked and annoyances were minor, several common and visible urban species, such as the House Sparrow (Passer domesticus), European Starling (Sturnus vulgaris), and Blue Jay (Cyanocitta cristata), may attract attention for their negative qualities, such as their sounds and effects on personal property. The results also indicate that residents' valuations of ecosystem services are linked to their perceptions of bird species richness rather than the actual species richness, and people may perceive only a subset of the birds in their neighborhoods. Although birds provide many important ecosystem services, perhaps one of their most important roles in cities is as a relatable and likable connecting point between city dwellers and the broader environment.

Scale-dependent and multi-metric nest habitat thresholds for Red-headed Woodpeckers at the northern periphery of their range
Jacob L. Berl, John W. Edwards, and Jeffrey S. Bolsinger

The relation between species occurrence and the structure or composition of habitat can be complex and often varies in a species-specific manner. Sometimes, species–habitat relations are defined by thresholds, or abrupt nonlinear responses to a habitat gradient. Threshold responses are expected when certain habitat features are required for species occurrence. For example, primary cavity-nesting woodpeckers often typify the threshold concept because in the absence of appropriate substrates (decadent wood) large enough for nest cavities, woodpeckers will not occur. In such cases, identifying thresholds is important to ensure that management activities meet minimal (or maximal) habitat requirements of target species. The Red-headed Woodpecker (Melanerpes erythrocephalus) is a species of national conservation concern, and loss of suitable nesting habitat has been suggested as a primary factor in its population declines. Threshold responses may partly explain why this species has gone locally extinct in areas where land-use change resulted in a transition from suitable to unsuitable habitat. Here, we tested whether a regionally important population of Red-headed Woodpeckers in northern New York, near the periphery of the species' range, exhibited threshold responses in their selection of nesting habitat. We used boosted regression trees (BRT) to identify nest habitat thresholds in relation to multiple habitat variables at multiple spatial scales (nest tree, forest patch, and forest stand). We identified nest tree thresholds related to tree decay class (≥33% decadent canopy), cumulative dead limb length (≥4 m), and tree diameter (≥34 cm dbh). Forest patch (vegetation surrounding nest tree; 0.04 ha) thresholds were related to cumulative dead limb length (≥17 m), woody understory height (<12 cm), mean tree diameter (30 cm dbh), and large tree (≥30 cm dbh) density of ≥4. Forest stand thresholds were related to overall stand decadence (on average trees have ≥1% crown decay) and woody understory height (<12 cm). Red-headed Woodpeckers exhibited scale-dependent and multi-metric nest habitat thresholds, which indicate that a lack of suitable nesting habitat (i.e. habitats meeting or exceeding multi-metric and multi-scale criteria) may be limiting population growth near the periphery of the species' range. In particular, the abundance of decadent (dead and decaying) tree resources appears to limit the distribution of suitable habitat. Our objective threshold criteria can be used to identify habitats of high conservation value for this species, or to identify specific habitat features that require management or restoration to increase suitable habitat for this threatened species.

Genomic single-nucleotide polymorphisms confirm that Gunnison and Greater sage-grouse are genetically well differentiated and that the Bi-State population is distinct 
Sara J. Oyler-McCance, R. Scott Cornman, Kenneth L. Jones, and Jennifer A. Fike

Sage-grouse are iconic, declining inhabitants of sagebrush habitats in western North America, and their management depends on an understanding of genetic variation across the landscape. Two distinct species of sage-grouse have been recognized, Greater (Centrocercus urophasianus) and Gunnison sage-grouse (C. minimus), based on morphology, behavior, and variation at neutral genetic markers. A parapatric group of Greater Sage-Grouse along the border of California and Nevada (“Bi-State”) is also genetically distinct at the same neutral genetic markers, yet not different in behavior or morphology. Because delineating taxonomic boundaries and defining conservation units is often difficult in recently diverged taxa and can be further complicated by highly skewed mating systems, we took advantage of new genomic methods that improve our ability to characterize genetic variation at a much finer resolution. We identified thousands of single-nucleotide polymorphisms (SNPs) among Gunnison, Greater, and Bi-State sage-grouse and used them to comprehensively examine levels of genetic diversity and differentiation among these groups. The pairwise multilocus fixation index (FST) was high (0.49) between Gunnison and Greater sage-grouse, and both principal coordinates analysis and model-based clustering grouped samples unequivocally by species. Standing genetic variation was lower within the Gunnison Sage-Grouse. The Bi-State population was also significantly differentiated from Greater Sage-Grouse, albeit more weakly (FST = 0.09), and genetic clustering results were consistent with reduced gene flow with Greater Sage-Grouse. No comparable genetic divisions were found within the Greater Sage-Grouse sample, which spanned the southern half of the range. Thus, we provide much stronger genetic evidence supporting the recognition of Gunnison Sage-Grouse as a distinct species with low genetic diversity. Further, our work confirms that the Bi-State population is differentiated from other Greater Sage-Grouse. The level of differentiation is much less than the divergence between Greater and Gunnison sage-grouse, supporting the idea that the Bi-State represents a unique population within the Greater Sage-Grouse. New genomic methods like the restriction-site-associated DNA (RAD-tag) method used here illustrate how increasing the number of markers and coverage of the genome can better characterize patterns of genetic variation, particularly among recently diverged taxa, providing vital information for conservation and management.

Occupancy of California Spotted Owl sites following a large fire in the Sierra Nevada, California
Derek E. Lee and Monica L. Bond

High-severity forest fire often is presumed to adversely affect the occupancy of territories by California Spotted Owls (Strix occidentalis occidentalis) because these owls are associated with mature and old-growth forests. We used single-season, multi-state occupancy statistics to estimate site occupancy probability for Spotted Owls at 45 historically occupied sites during the breeding season immediately following the 2013 Rim Fire, which was one of the largest forest fires on record in California. We quantified how occupancy probability was influenced by the amount of high-severity fire occurring in mature forested habitat within Protected Activity Centers (PACs). The model-averaged estimate of site-occupancy probability for at least a single owl was 0.922 (±SE = 0.073), which was higher than other published occupancy probability estimates for this subspecies in either burned or long-unburned sites in the Sierra Nevada. Mean site-occupancy probability for pairs was 0.866 (±0.093), and most sites (33) were occupied by pairs. The amount of high-severity fire in the PAC did not affect pair occupancy. Occupancy probability by at least a single bird was negatively correlated with the amount of high severity fire in the PAC but remained >0.89 in 100% high-severity burned PACs. These data add to observations that California Spotted Owls continue to use post-fire landscapes, even when the fires were large and where large areas burned at high severity, suggesting that owls are not generally negatively impacted by high-severity fire. Based on this and other studies of Spotted Owls, fire, and logging, we suggest land managers consider burned forest within and surrounding PACs as potentially suitable California Spotted Owl foraging habitat when planning and implementing management activities, and we recommend against logging burned forest within at least 1.5 km of nests or roosts for the conservation and recovery of this declining subspecies.

Reproductive performance of Kittlitz's Murrelet in a glaciated landscape, Icy Bay, Alaska, USA
Michelle L. Kissling, Scott M. Gende, Stephen B. Lewis, and Paul M. Lukacs

Kittlitz's Murrelet (Brachyramphus brevirostris) is a dispersed-nesting seabird endemic to Alaska and eastern Russia that may have experienced considerable population declines in some parts of its range in the past few decades. Poor reproduction has been suggested as the demographic bottleneck, yet there are no direct estimates of reproduction in a glaciated area where this species reaches its highest densities at sea during the breeding season. The lack of demographic information in glacial habitats has limited our ability to interpret population trends and to clarify whether the presence of glaciers affects reproductive performance. Between 2007 and 2012, we radio-tagged Kittlitz's Murrelets to measure breeding propensity, nesting success, and fecundity in the heavily glaciated landscape of Icy Bay, Alaska, USA. Of 156 radio-tagged birds, 20% were breeders, 68% were potential breeders, and 12% were nonbreeders. Radio-tagged males (29%) were more likely to be breeders compared to females (11%). Across all years, we located 34 Kittlitz's Murrelet nests, 38% of which were successful. Daily nest survival probability (± SE) was 0.979 ± 0.005, with most nests failing during incubation; if extrapolated to a 55-day period from nest initiation to fledging, the nest survival rate was 0.307 ± 0.083. Low fecundity was due largely to low breeding propensity, not low nesting success. For context, we also determined the breeding status of 14 radio-tagged Marbled Murrelets (B. marmoratus), most of which were breeders (79%) and successfully fledged young (69%). Our data demonstrated that Kittlitz's Murrelets were outperformed in all facets of reproduction compared to Marbled Murrelets. Low fecundity estimates for Kittlitz's Murrelet were consistent with a 10% per annum decline in Icy Bay between 2002 and 2012, suggesting that poor reproductive performance contributed to the local population decline of this species.

Minimizing marker mass and handling time when attaching radio-transmitters and geolocators to small songbirds 
Henry M. Streby, Tara L. McAllister, Sean M. Peterson, Gunnar R. Kramer, Justin A. Lehman, and David E. Andersen

Radio-transmitters and light-level geolocators are currently small enough for use on songbirds weighing <15 g. Various methods are used to attach these markers to larger songbirds, but with small birds it becomes especially important to minimize marker mass and bird handling time. Here, we offer modifications to harness materials and marker preparation for transmitters and geolocators, and we describe deployment methods that can be safely completed in 20–60 s per bird. We describe a 0.5-mm elastic sewing thread harness for radio-transmitters that allows nestlings, fledglings, and adults to be marked with the same harness size and reliably falls off to avoid poststudy effects. We also describe a 0.5-mm jewelry cord harness for geolocators that provides a firm fit for >1 yr. Neither harness type requires plastic or metal tubes, rings, or other attachment fixtures on the marker, nor do they require crimping beads, epoxy, scissors, or tying knots while handling birds. Both harnesses add 0.03 g to the mass of markers for small wood-warblers (Parulidae). This minimal additional mass is offset by trimming transmitter antennas or geolocator connection nodes, resulting in no net mass gain for transmitters and 0.02 g added for geolocators compared with conventional harness methods that add >0.40 g. We and others have used this transmitter attachment method with several small songbird species, with no effects on adult and fledgling behavior and survival. We have used this geolocator attachment method on 9-g wood-warblers with no effects on return rates, return dates, territory fidelity, and body mass. We hope that these improvements to the design and deployment of the leg-loop harness method will enable the safe and successful use of these markers, and eventually GPS and other tags, on similarly small songbirds.

Geolocators on Golden-winged Warblers do not affect migratory ecology
Sean M. Peterson, Henry M. Streby, Gunnar R. Kramer, Justin A. Lehman, David A. Buehler, and David E. Andersen

The use of light-level geolocators is increasingly common for connecting breeding and nonbreeding sites and identifying migration routes in birds. Until recently, the mass and size of geolocators precluded their use on songbird species weighing <12 g. Reducing the mass of geolocators, such as by shortening or eliminating the light stalk, may make their deployment on small birds feasible, but may also inhibit their ability to receive light reliably, because small geolocators can be shaded by feathers. Here we report geolocator effects on migratory ecology of Golden-winged Warblers (Vermivora chrysoptera) in Minnesota and Tennessee. We also evaluated whether stalk length influenced precision of location data for birds on the breeding grounds. At 8–10 g, Golden-winged Warblers are the smallest birds to be outfitted with geolocators to date. We found no differences in return rates, inter-annual territory fidelity, or body mass between geolocator-marked individuals and a control group of color-banded individuals. We observed no difference in return rates or variation in estimated breeding locations between birds marked with stalked geolocators and those with stalkless geolocators. Our results suggest that some small songbirds can be safely marked with geolocators. Light stalks appear to be unnecessary for Golden-winged Warblers; the added mass and drag of stalks can probably be eliminated on other small songbirds.

Recreation changes the use of a wild landscape by corvids 
Lauren E. Walker and John M. Marzluff

As urban areas have grown in population, use of nearby natural areas for outdoor recreation has also increased, potentially influencing bird distribution in landscapes managed for conservation. Members of the family Corvidae (crows, ravens, jays, and magpies) have strong interactions with humans and may be directly affected by recreation in wild landscapes. In Mount Rainier National Park, we evaluated the effects of vegetation, visitor use, and the availability of human-subsidized food on the use of landscape features by 4 corvid species: Steller's Jay (Cyanocitta stelleri), Gray Jay (Perisoreus canadensis), Common Raven (Corvus corax), and Clark's Nutcracker (Nucifraga columbiana). We conducted >1,400 point counts across areas that varied in habitat and in the degree of human recreational impact. We calculated predicted occupancy values while allowing for variation in detection probability. In addition to species-specific suites of vegetation and landscape variables, we found that patterns of human recreation, such as visitor use, food subsidy, and amount of road edge, were also significant in explaining corvid distribution. The number of visitors present during point counts was positively associated with Steller's Jay and Clark's Nutcracker use. Common Ravens used areas with fewer people but with a high density of road edge. Gray Jays, Common Ravens, and Clark's Nutcrackers were each more likely to use sites with anthropogenic food subsidy than sites without subsidies. These changes in landscape use may affect the performance of ecosystem services by corvids and could serve as useful and easily measured bioindicators of the impacts of recreation.

Responses of male Greater Prairie-Chickens to wind energy development
Virginia L. Winder, Andrew J. Gregory, Lance B. McNew, and Brett K. Sandercock

Renewable energy resources have received increased attention because of impacts of fossil fuels on global climate change. In Kansas, USA, optimal sites for wind energy development often overlap with preferred habitats of the Greater Prairie-Chicken (Tympanuchus cupido), a lek-mating prairie grouse of conservation concern. We tested for potential effects of energy development on male Greater Prairie-Chickens in north-central Kansas. We captured males at 23 leks located 0.04 to 28 km from wind turbines during a 2-yr preconstruction period (2007–2008) and a 3-yr postconstruction period (2009–2011). First, we tested for effects of proximity to turbines, habitat, and lek size on annual probability of lek persistence and changes in male numbers. We predicted that energy development might result in behavioral avoidance of areas close to turbines, resulting in increased rates of lek abandonment and fewer males attending surviving leks. We found that distance to turbine had a negative effect on lek persistence for leks <8 km from turbines during the postconstruction period, supporting the 8-km buffer zone recommended by the U.S. Fish and Wildlife Service as an offset for wind energy projects. Additionally, lek persistence was positively related to number of males counted at a lek and with grassland cover surrounding the lek. Second, we tested for effects of wind energy development on male body mass. We predicted that degraded habitat conditions might result in decreased body mass for males attending leks near turbines during the postconstruction period. Male body mass was ~2% lower during the postconstruction period, but distance to turbine did not affect body mass. Additional study is needed to determine whether short-term effects of turbines on lek persistence influence population viability of Greater Prairie-Chickens.

When to use social cues: Conspecific attraction at newly created grasslands
John E. Andrews, Jeffrey D. Brawn, and Michael P. Ward

Social cues are often used by birds when selecting breeding habitats, however, little is known about the timing and influence of social cues within or across seasons. The ontogeny of social information within newly available habitat is essentially unknown and potentially relevant to habitat management, as the primary approach of many conservation initiatives is to simply create habitat. We investigated the influence of conspecific attraction via social cues (conspecific playbacks) on newly created grasslands for Grasshopper Sparrows (Ammodramus savannarum) in Central Illinois over a 2-year period. We found that Grasshopper Sparrows quickly locate and settle at newly created grasslands without the need for social cues, however, social cues are used later in the season. At sites where social cues (i.e. conspecific vocalizations) were broadcast the densities of Grasshopper Sparrows were nearly double that of sites without the additional social cues, however, this difference occurred later in the breeding season. We suggest that social cues are more valuable for Grasshopper Sparrows later in the breeding season as a potential cue of the reproductive success of individuals currently at the site, and therefore future reproduction at the site. Grassland birds are experiencing large population declines and the primary conservation approach is to provide additional habitat. By understanding how grassland birds select breeding sites we can better develop and implement conservation plans.