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Monday, 30 June 2014

Ornithological Science: June 2014, Volume 13, Issue 1: Contents and Abstracts



Ornithological Science
Published by: The Ornithological Society of Japan

Table of Contents
June 2014 
Volume 13 Issue 1 
LINK




ORIGINAL ARTICLE

Foraging Tactics and Success of Inter- and Intra-Specific Kleptoparasites on Rhinoceros Auklets Cerorhinca monocerata

Masayuki Senzaki, Yuya Suzuki and Yutaka Watanuki
pg(s) 1–8

Abstract
Diurnal gulls and skuas, which depend mostly on visual cues during kleptoparasitic attacks, experience reduced predation success when low light conditions or dense vegetation impair prey visibility. Rhinoceros Auklets Cerorhinca monocerata lose prey to kleptoparasitic conspecifics and kleptoparasitic gulls. The return of adult auklets to their colony was observed and incidences of inter- and intra-specific kleptoparasitism were recorded in five study sites with high and low vegetation coverage under variable conditions of illumination. Whereas gulls (Black-tailed Larus crassirostris and Slaty-backed L. schistisagus) mainly attacked auklets in flight in the early evening and from distances exceeding five metres, auklets attacked later in the evening after auklet numbers on the ground had increased, and only when closer than two metres. Intra-specific kleptoparasitism occurred less frequently in sites with dense vegetation and where the visible range was short. These findings indicate that environmental factors facilitating kleptoparasitism among gulls (aerial pirates) and auklets (close-quarter terrestrial pirates) are different.


Gender Identification by Calls and Body Size of the Streaked Shearwater Examined by CHD Genes

Hiroshi Arima, Nariko Oka, Yoshiyuki Baba, Hisashi Sugawa and Takahiro Ota
pg(s) 9–17

Abstract
Like most seabirds Streaked Shearwaters Calonectris leucomelas have sexually monomorphic plumage. Researchers have conveniently identified gender in the field by means of two types of calls, associated with dimorphism in body size. By molecular sexing analysis using the chromo-helicase-DNA-binding (CHD) genes, we determined the gender of Streaked Shearwaters in relation to call types and body size. We recorded the type of calls, measured body dimensions and collected non-invasive samples (buccal cells or feathers) of Streaked Shearwaters at two breeding islands. As obvious amplification to identify gender by polymerase chain reaction (PCR) could not be obtained at high rates using a known universal primer pair, we developed two new primer pairs to identify gender in this species; this enabled us to identify the gender of all of the samples. Without exception all males gave high-pitched calls, whereas all females gave low-pitched calls. Molecular evidence also confirmed morphometric differences between males and females. We, therefore, conclude that Streaked Shearwaters exhibit sexual dimorphism in body size and call type. Males are significantly larger than females, and males give high calls whereas females give low calls.



Molecular Cloning of Glucocorticoid and Mineralocorticoid Receptors in Eurasian Tree Sparrow Passer montanus

Chao DU, Bei QIAO, Yaqing LI, Yao YAO, Lina WU, Shuo CUI, Xuelu LIU, Yinchao HAO, Dongming LI and Yuefeng WU
pg(s) 19–27

Abstract
Glucocorticoids mediate various essential biological functions by binding to and activating their specific receptors. In vertebrates, interactions between glucocorticoid receptors (GR) and mineralocorticoid receptors (MR) play an important role in the feedback pathways of glucocorticoid regulation. In free-living birds, a number of studies have demonstrated seasonal regulation of the adrenocortical response to stress, but little is known about their downstream receptors, GR and MR. In this study, we successfully cloned the full-length open reading frames (ORFs) of the GR (eGR) and the MR (eMR) cDNAs from a passerine species, the Eurasian Tree Sparrow Passer montanus. The ORFs eGR contains 2,322 base pairs encoding 773 amino acids, and the eMR contains 2,952 base pairs encoding 983 amino acids. The eGR and eMR are highly conserved in their gene and amino acid sequences and in their secondary and 3D structures when compared with other species of birds and vertebrates.



Population Trends of Grassland Birds in Hokkaido, Focussing on the Drastic Decline of the Yellow-breasted Bunting

Katsumi Tamada, Masaaki Tomizawa, Masatoshi Umeki and Masayuki Takada
pg(s) 29–40

Abstract
To examine the population trends of grassland and shrub birds in Hokkaido, we conducted line transect censuses in 2002 and 2003, in area where avifaunal studies had been performed in the 1970s and 1980s. To document the decline in the Yellow-breasted Bunting Emberiza aureola, birdwatching data were also analysed. The Yellow-breasted Bunting population has decreased drastically both in density and in distribution over the intervening thirty years. The decline in occupied breeding sites and in the population is continuing. Densities of Eurasian Skylark Alauda arvensis and Lanceolated Grasshopper Warbler Locustella lanceolata have also declined, although their range contractions are not yet severe. The ranges of Brown Shrike Lanius cristatus and Chestnut-eared Bunting E. fucata appear to have contracted. In contrast, data analysis revealed that the breeding range of Yellow Wagtail Motacilla flava has expanded in northern Hokkaido, but it is possible that the range had expanded in the past but had been overlooked. The present study suggests that the ranges of Bull-headed Shrike L. bucephalus and Gray's Grasshopper Warbler L. fasciolata had expanded, although some previous studies do not support this trend. In this study we were not able to clarify the reason why the population trends of these species have changed. Further research is necessary focussing on: breeding habitat analysis, breeding biology in relation to population trends, population trends in wintering and migration areas and clarification of migration routes. The population decline in the Yellow-breasted Bunting is both dramatic and very severe. This migratory species in particular requires immediate international conservation measures to avoid national and regional extinction.



SHORT COMMUNICATION

Do Introduced Mammals Chronically Impact the Breeding Success of the World'S Rarest Albatross?

Jean-Baptiste Thiebot, Christophe Barbraud, Karine Delord, Cédric Marteau and Henri Weimerskirch
pg(s) 41–46

Abstract
Introduced mammals may have deleterious effects on avifauna. We investigated whether such species may be affecting the breeding success of the critically endangered Amsterdam Albatrosses Diomedea amsterdamensis on its remote breeding island. Twelve camera-traps deployed near albatross nests during the chick brooding period in 2011 captured 25,000 pictures. Two of them showed Black Rats Rattus rattus, but without revealing evidence of any direct interaction between the two species. Breeding success in 2011 was similar to that in previous years (60%). Our survey suggests that introduced mammals may not currently represent a primary direct threat to this population, but they might amplify the risks of chick mortality in case of disease outbreaks.



The First Record of Brood Parasitism on the Introduced Red-Billed Leiothrix in Japan

Hitoshi Tojo and Syuya Nakamura
pg(s) 47–52

Abstract
The Red-billed Leiothrix Leiothrix lutea has been introduced to, and become established in Japan, the Hawaiian Islands and certain areas of Europe. Unlike in its native range, introduced Red-billed Leiothrix populations have not been observed to be hosts of avian brood parasites. We found a parasite egg with three host eggs in a Red-billed Leiothrix nest on 14 July 2010 on Mt Tsukuba, central Japan. Despite its marked difference from the host eggs, the parasite egg was accepted and incubated by the l Red-billed Leiothrix parent until the nest was depredated before hatching. The morphology of the parasite egg suggested that it belonged to Oriental Cuckoo Cuculus optatus.

Bird research this week on PubMed: June 2014 Week 4

PubMed listing for 'bird' OR 'songbird' excluding references to influenza and flu - June 2014 Week 4




1. PLoS One. 2014 Jun 27;9(6):e100802. doi: 10.1371/journal.pone.0100802. eCollection 2014.

Host Competence and Helicase Activity Differences Exhibited by West Nile Viral Variants Expressing NS3-249 Amino Acid Polymorphisms.

Langevin SA1, Bowen RA2, Reisen WK1, Andrade CC1, Ramey WN1, Maharaj PD1, Anishchenko M3, Kenney JL3, Duggal NK3, Romo H3, Bera AK4, Sanders TA5, Bosco-Lauth A6, Smith JL7, Kuhn R4, Brault AC8.Author information:
1Center for Vectorborne Diseases and Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America.
2Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America.
3Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America.
4Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America.
5United States Fish and Wildlife Service, Portland, Oregon, United States of America.
6Department of 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.
7Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, United States of America.
8Center for Vectorborne Diseases and Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America; Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America.

Abstract

A single helicase amino acid substitution, NS3-T249P, has been shown to increase viremia magnitude/mortality in American crows (AMCRs) following West Nile virus (WNV) infection. Lineage/intra-lineage geographic variants exhibit consistent amino acid polymorphisms at this locus; however, the majority of WNV isolates associated with recent outbreaks reported worldwide have a proline at the NS3-249 residue. In order to evaluate the impact of NS3-249 variants on avian and mammalian virulence, multiple amino acid substitutions were engineered into a WNV infectious cDNA (NY99; NS3-249P) and the resulting viruses inoculated into AMCRs, house sparrows (HOSPs) and mice. Differential viremia profiles were observed between mutant viruses in the two bird species; however, the NS3-249P virus produced the highest mean peak viral loads in both avian models. In contrast, this avian modulating virulence determinant had no effect on LD50 or the neurovirulence phenotype in the murine model. Recombinant helicase proteins demonstrated variable helicase and ATPase activities; however, differences did not correlate with avian or murine viremia phenotypes. These in vitro and in vivo data indicate that avian-specific phenotypes are modulated by critical viral-host protein interactions involving the NS3-249 residue that directly influence transmission efficiency and therefore the magnitude of WNV epizootics in nature.
PMID: 24971589 [PubMed - as supplied by publisher]


2. Ecol Evol. 2014 May;4(9):1659-70. doi: 10.1002/ece3.1059. Epub 2014 Apr 8.

Estimating migratory connectivity of birds when re-encounter probabilities are heterogeneous.

Cohen EB1, Hostetler JA1, Royle JA2, Marra PP1.Author information:
1Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park Washington, District of Columbia.
2U.S. Geological Survey, Patuxent Wildlife Research Center Laurel, Maryland.

Abstract

Understanding the biology and conducting effective conservation of migratory species requires an understanding of migratory connectivity - the geographic linkages of populations between stages of the annual cycle. Unfortunately, for most species, we are lacking such information. The North American Bird Banding Laboratory (BBL) houses an extensive database of marking, recaptures and recoveries, and such data could provide migratory connectivity information for many species. To date, however, few species have been analyzed for migratory connectivity largely because heterogeneous re-encounter probabilities make interpretation problematic. We accounted for regional variation in re-encounter probabilities by borrowing information across species and by using effort covariates on recapture and recovery probabilities in a multistate capture-recapture and recovery model. The effort covariates were derived from recaptures and recoveries of species within the same regions. We estimated the migratory connectivity for three tern species breeding in North America and over-wintering in the tropics, common (Sterna hirundo), roseate (Sterna dougallii), and Caspian terns (Hydroprogne caspia). For western breeding terns, model-derived estimates of migratory connectivity differed considerably from those derived directly from the proportions of re-encounters. Conversely, for eastern breeding terns, estimates were merely refined by the inclusion of re-encounter probabilities. In general, eastern breeding terns were strongly connected to eastern South America, and western breeding terns were strongly linked to the more western parts of the nonbreeding range under both models. Through simulation, we found this approach is likely useful for many species in the BBL database, although precision improved with higher re-encounter probabilities and stronger migratory connectivity. We describe an approach to deal with the inherent biases in BBL banding and re-encounter data to demonstrate that this large dataset is a valuable source of information about the migratory connectivity of the birds of North America.
PMID: 24967083 [PubMed]
Related citations

3. Ecol Evol. 2014 May;4(9):1589-600. doi: 10.1002/ece3.1049. Epub 2014 Mar 31.

Power lines, roads, and avian nest survival: effects on predator identity and predation intensity.

DeGregorio BA1, Weatherhead PJ1, Sperry JH2.Author information:
1Department of Natural Resources and Environmental Sciences, University of Illinois 1102 S. Goodwin Ave, Urbana, Illinois, 61801.
2 Department of Natural Resources and Environmental Sciences, University of Illinois 1102 S. Goodwin Ave, Urbana, Illinois, 61801 ; Engineer Research and Development Center Champaign, IL.

Abstract

1 Anthropogenic alteration of landscapes can affect avian nest success by influencing the abundance, distribution, and behavior of predators. Understanding avian nest predation risk necessitates understanding how landscapes affect predator distribution and behavior. 2 From a sample of 463 nests of 17 songbird species, we evaluated how landscape features (distance to forest edge, unpaved roads, and power lines) influenced daily nest survival. We also used video cameras to identify nest predators at 137 nest predation events and evaluated how landscape features influenced predator identity. Finally, we determined the abundance and distribution of several of the principal predators using surveys and radiotelemetry. 3 Distance to power lines was the best predictor of predator identity: predation by brown-headed cowbirds (Molothrus ater), corvids (Corvus sp. and Cyanocitta cristata), racers (Coluber constrictor), and coachwhips (Masticophis flagellum) increased with proximity to power lines, whereas predation by rat snakes (Elaphe obsoleta) and raptors decreased. In some cases, predator density may reliably indicate nest predation risk because racers, corvids, and cowbirds frequently used power line right-of-ways. 4 Of five bird species with enough nests to analyze individually, daily nest survival of only indigo buntings (Passerina cyanea) decreased with proximity to power lines, despite predation by most predators at our site being positively associated with power lines. For all nesting species combined, distance to unpaved road was the model that most influenced daily nest survival. This pattern is likely a consequence of rat snakes, the locally dominant nest predator (28% of predation events), rarely using power lines and associated areas. Instead, rat snakes were frequently associated with road edges, indicating that not all edges are functionally similar. 5 Our results suggest that interactions between predators and landscape features are likely to be specific to both the local predators and landscape. Thus, predicting how anthropogenic changes to landscapes affect nesting birds requires that we know more about how landscape changes affect the behavior of nest predators and which nest predators are locally important.
PMID: 24967077 [PubMed]
Related citations

4. Front Behav Neurosci. 2014 Jun 11;8:210. doi: 10.3389/fnbeh.2014.00210. eCollection 2014.

Sexually dimorphic activation of dopaminergic areas depends on affiliation during courtship and pair formation.

Iwasaki M1, Poulsen TM2, Oka K3, Hessler NA2.Author information:
1RIKEN Brain Science Institute Wako-shi, Japan ; Department of Biology, Keio University Yokohama, Japan.
2RIKEN Brain Science Institute Wako-shi, Japan.
3Department of Biology, Keio University Yokohama, Japan.

Abstract

For many species, dyadic interaction during courtship and pair bonding engage intense emotional states that control approach or avoidance behavior. Previous studies have shown that one component of a common social brain network (SBN), dopaminergic areas, are highly engaged during male songbird courtship of females. We tested whether the level of activity in dopaminergic systems of both females and males during courtship is related to their level of affiliation. In order to objectively quantify affiliative behaviors, we developed a system for tracking the position of both birds during free interaction sessions. During a third successive daily interaction session, there was a range of levels of affiliation among bird pairs, as quantified by several position and movement parameters. Because both positive and negative social interactions were present, we chose to characterize affiliation strength by pair valence. As a potential neural system involved in regulating pair valence, the level of activity of the dopaminergic group A11 (within the central gray) was selectively reduced in females of positive valence pairs. Further, activation of non-dopaminergic neurons in VTA was negatively related to valence, with this relationship strongest in ventral VTA of females. Together, these results suggest that inhibition of fear or avoidance networks may be associated with development of close affiliation, and highlight the importance of negative as well as positive emotional states in the process of courtship, and in development of long-lasting social bonds.
PMID: 24966819 [PubMed]
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5. Proc Biol Sci. 2014 Aug 7;281(1788). pii: 20140806. doi: 10.1098/rspb.2014.0806.

Ancient origins and multiple appearances of carotenoid-pigmented feathers in birds.

Thomas DB1, McGraw KJ2, Butler MW3, Carrano MT4, Madden O5, James HF6.Author information:
1Department of Vertebrate Zoology, MRC-116, Smithsonian Institution, Washington, DC 20013-7012, USA Museum Conservation Institute, Smithsonian Institution, Suitland, MD 20746, USA Institute of Natural and Mathematical Sciences, Massey University, Auckland 0632, New Zealand d.b.thomas@massey.ac.nz.
2School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA.
3Department of Biology, Lafayette College, Easton, PA 18042-1778, USA.
4Department of Paleobiology, MRC-121, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA.
5Museum Conservation Institute, Smithsonian Institution, Suitland, MD 20746, USA.
6Department of Vertebrate Zoology, MRC-116, Smithsonian Institution, Washington, DC 20013-7012, USA.

Abstract

The broad palette of feather colours displayed by birds serves diverse biological functions, including communication and camouflage. Fossil feathers provide evidence that some avian colours, like black and brown melanins, have existed for at least 160 million years (Myr), but no traces of bright carotenoid pigments in ancient feathers have been reported. Insight into the evolutionary history of plumage carotenoids may instead be gained from living species. We visually surveyed modern birds for carotenoid-consistent plumage colours (present in 2956 of 9993 species). We then used high-performance liquid chromatography and Raman spectroscopy to chemically assess the family-level distribution of plumage carotenoids, confirming their presence in 95 of 236 extant bird families (only 36 family-level occurrences had been confirmed previously). Using our data for all modern birds, we modelled the evolutionary history of carotenoid-consistent plumage colours on recent supertrees. Results support multiple independent origins of carotenoid plumage pigmentation in 13 orders, including six orders without previous reports of plumage carotenoids. Based on time calibrations from the supertree, the number of avian families displaying plumage carotenoids increased throughout the Cenozoic, and most plumage carotenoid originations occurred after the Miocene Epoch (23 Myr). The earliest origination of plumage carotenoids was reconstructed within Passeriformes, during the Palaeocene Epoch (66-56 Myr), and not at the base of crown-lineage birds.
© 2014 The Author(s) Published by the Royal Society. All rights reserved.
PMID: 24966316 [PubMed - in process]
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6. Proc Biol Sci. 2014 Aug 7;281(1788). pii: 20140765. doi: 10.1098/rspb.2014.0765.

The developmental origin of zygodactyl feet and its possible loss in the evolution of Passeriformes.

Botelho JF1, Smith-Paredes D2, Nuñez-Leon D2, Soto-Acuña S3, Vargas AO2.Author information:
1Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Universidad de Chile, Las Palmeras, 3425, Santiago, RM, Chile joaofranciscobotelho@gmail.com.
2Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Universidad de Chile, Las Palmeras, 3425, Santiago, RM, Chile.
3Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Universidad de Chile, Las Palmeras, 3425, Santiago, RM, Chile Área de Paleontología, Museo Nacional de Historia Natural, Santiago, RM, Chile.

Abstract

The zygodactyl orientation of toes (digits II and III pointing forwards, digits I and IV pointing backwards) evolved independently in different extant bird taxa. To understand the origin of this trait in modern birds, we investigated the development of the zygodactyl foot of the budgerigar (Psittaciformes). We compared its muscular development with that of the anisodactyl quail (Galliformes) and show that while the musculus abductor digiti IV (ABDIV) becomes strongly developed at HH36 in both species, the musculus extensor brevis digiti IV (EBDIV) degenerates and almost disappears only in the budgerigar. The asymmetric action of those muscles early in the development of the budgerigar foot causes retroversion of digit IV (dIV). Paralysed budgerigar embryos do not revert dIV and are anisodactyl. Both molecular phylogenetic analysis and palaeontological information suggest that the ancestor of passerines could have been zygodactyl. We followed the development of the zebra finch (Passeriformes) foot muscles and found that in this species, both the primordia of the ABDIV and of the EBDIV fail to develop. These data suggest that loss of asymmetric forces of muscular activity exerted on dIV, caused by the absence of the ABDIV, could have resulted in secondary anisodactyly in Passeriformes.
© 2014 The Author(s) Published by the Royal Society. All rights reserved.
PMID: 24966313 [PubMed - in process]
Related citations

7. Neurotox Res. 2014 Jun 26. [Epub ahead of print]

DSP4, a Selective Neurotoxin for the Locus Coeruleus Noradrenergic System. A Review of Its Mode of Action.

Ross SB1, Stenfors C.Author information:
1AstraZeneca R&D, Södertälje, Sweden.

Abstract

DSP4 (N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride) is a selective neurotoxin for the locus coeruleus noradrenergic system in the rodent and bird brain. It readily passes the blood-brain barrier and cyclizes to a reactive aziridinium derivative that is accumulated into the noradrenergic nerve terminals via the noradrenaline transporter. DSP4 is also an irreversible inhibitor of this transporter. Within the nerve terminals the aziridinium derivative reacts with unknown vital cellular components, destroying the terminals. At the dose 50 mg/kg i.p. this is characterized by a rapid and long-lasting loss of noradrenaline and a slower decrease in the dopamine-β-hydroxylase enzyme activity and immunoreactivity in the regions innervated from locus coeruleus. The tissue level of noradrenaline is reduced to 10-30 % of the normal value. The extraneuronal concentration is, on the other hand, increased due to inflow from non-lesioned regions. Like the peripheral sympathetic nerves the non-locus coeruleus noradrenergic systems in the rodent brain is resistant to the neurotoxic action of DSP4. Serotoninergic and dopaminergic nerves are only slightly or not at all affected by DSP4. The neurotoxic effect is counteracted by pretreatment with noradrenaline uptake inhibitors (e.g., desipramine). MAO-B inhibitors of the N-propargylamine type (e.g., selegiline) also counteract the DSP4-induced neurotoxicity with another, yet unknown mechanism. Because of its selectivity for the locus coeruleus system DSP4 is a useful tool in studies of the functional role of this noradrenergic system in the brain.
PMID: 24964753 [PubMed - as supplied by publisher]
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Thursday, 26 June 2014

Ardeola Journal: June 2014, Volume 61, Issue 1: Contents and Abstracts

Ardeola

Published by: Spanish Society of Ornithology/BirdLife





Table of Contents

June 2014 : Volume 61 Issue 1

ARTICLES

Demographic and Breeding Performance of a New Kelp Gull Larus dominicanus Colony in Patagonia, Argentina Full Access
Nora Lisnizer , Pablo García-Borboroglu and Pablo Yorio
pg(s) 3–14


 Abstract
Understanding the processes involved in the establishment and persistence of new seabird colonies is important for improving conservation and management strategies. Over the past few decades, kelp gull Larus dominicanus numbers have increased in Patagonia, Argentina, and new colonies have been reported. We studied a recently established colony to analyse aspects of its population dynamics and breeding biology. The number of breeding pairs at Punta Loma increased from 13 to 233 in the seven years after the colony was established (2004–2011) and the number of chicks fledged per nest was low (< 1 chick per nest) compared to that of other long-established kelp gull colonies in the region. Modelled estimates of abundance assuming closed population dynamics for the Punta Loma colony were lower than observed (70% lower or more), suggesting that the observed growth cannot be explained by local productivity alone. Immigration from other colonies was likely to be the main factor responsible for the observed growth, being considerably higher than local recruitment. This study constitutes the first characterisation of demographic processes occurring during the initial years following colony establishment in kelp gulls. The main findings include rapid population growth driven by immigration and poor breeding performance potentially linked to a high proportion of young breeders. Our results highlight the key role of source-sink dynamics on the growth and persistence of new seabird colonies.
Abstract & References : Full Text : PDF (191 KB) 

Age and Sex Differences in Fuel Load and Biometrics of Aquatic Warblers Acrocephalus paludicola at an Autumn Stopover Site in the Loire Estuary (NW France) Full Access
Dariusz Jakubas , Katarzyna Wojczulanis-Jakubas , Julien Foucher, Joanna Dziarska-Pałac and Hubert Dugué
pg(s) 15–30


 Abstract

The aquatic warbler Acrocephalus paludicola is the only globally threatened passerine breeding in Europe. We studied morphometric traits of 176 individuals captured at one of the key European autumn stopover sites, the Loire estuary on the Atlantic coast of France, in relation to age (first-year and older) and sex (based on molecular determination). We found significant sex differences in wing length, third primary feather length and body mass, with males being longer-winged and heavier than females; adult females also had deeper bills. However, high overlap in all measurements between the sexes meant the best discriminant functions based on wing length and bill depth (adults) and wing length (inmatures) correctly classified only 87% and 75% of individuals, respectively. The mean potential non-stop flight range of autumn staging birds at the Loire estuary with high fuel load was estimated at 1,178 km for adults and 926 km for immatures. We conclude that in autumn migrant aquatic warblers probably do not fly directly to wintering grounds in west Africa. Instead they gain significant body mass for onward migration at a few key stopover sites in western Europe and the southern Mediterranean region. Conservation of a series of important refuelling stopover sites, especially wet grassland habitats, along the migration route is therefore essential for effective protection of the aquatic warbler.
Abstract & References : Full Text : PDF (365 KB) 

Habitat-Related Effects on Temporal Variations in Red-Legged Partridge Alectoris rufa Abundance Estimations in Olive Groves Full Access
Jesús Duarte, Miguel Ángel Farfán, John E. Fa and Juan Mario Vargas
pg(s) 31–43


Abstract
Surveys are very important tools for population monitoring, conservation and species management. Censuses aid in the sustainable harvesting of game species. Our aim in this study was to test whether some factors related to habitat and agricultural practices of olive cultivation may influence red-legged partridge abundance estimates. We investigated the effects of time of day and season of the year in which censuses are conducted, as well as of the reduction of herbaceous cover and the installation of irrigation systems, on red-legged partridge abundance estimates. In surveys conducted in winter, no differences were found in the estimates of abundance and density between partridge censuses at dawn and dusk. In surveys conducted in summer, the estimates made at dusk were significantly higher than those at dawn. The coefficients of variation of the estimates were lower at dusk in the two seasons. In winter, partridge abundance was not related to any of the factors studied. However, in summer partridge observations were related to the distances to the border of the olive grove, where herbaceous vegetation persists, and to water sources. There was an interaction between the time of the census and the habitat preferences of partridges. During the morning, partridges were more active and moved towards the borders of the grove. At dusk partridges were less active and returned to the olive grove. The results suggest that habitat use by red-legged partridges undergoes spatial and temporal adjustments in olive groves that seem to be related to some habitat features of the groves associated with agricultural practices. The temporal and spatial behaviour of the birds in the groves can influence the accuracy of surveys. Differences in the results of censuses carried out at dawn and dusk indicate that the two may not be comparable and suggest the need to take time of day into account when designing a survey.
Abstract & References : Full Text : PDF (561 KB)

Spatial Patterns of Genetic Diversity in Mediterranean Eagle Owl Bubo bubo Populations Full Access
Mario León-Ortega, Mercedes González-Wangüemert, José E. Martínez and José F. Calvo
pg(s) 45–62


Abstract

Little information is available on the patterns of genetic connectivity in owls. We studied the genetic structure of the eagle owl Bubo bubo (Linnaeus, 1758) in southeastern Spain at two different spatial scales. Seven microsatellites previously described for this species were used, although only six loci amplified correctly. The observed low genetic variation could be explained by the short dispersal distance, high mortality rate and high degree of monogamy shown by this large nocturnal predator. As expected, the highest genetic isolation was detected in the geographically most isolated population. Significant genetic differentiation was found among study units separated by less than 50 km. The territorial analysis showed interesting connectivity patterns related with the gene flow and turnover rate of the breeding individuals. The lowest genetic diversity was found in the region with the largest population, which could imply incipient inbreeding.

Abstract & References : Full Text : PDF (339 KB)

Reverse Movements of Red Knots Calidris canutus During Northward Migration in Argentina Full Access
Verónica L. D'Amico, Patricia M. González , R. I. Guy Morrison and Allan J. Baker
pg(s) 63–76


Abstract

Migratory birds are sometimes known to make reverse movements to seek better fuelling sites before undertaking long-distance migratory flights across ecological barriers. Red knots Calidris canutus rufa regularly make prodigious migratory flights of ∼ 8,000 km from southern South America to North America; these flights depend critically on the birds being able to store adequate fuel at southern staging sites. Knots staging at San Antonio Oeste (SAO) in northern Patagonia in Argentina could potentially backtrack ∼200 km southwards to complete refuelling at Península Valdés (PV). We therefore analysed resightings of birds individually marked in SAO or the flyway at these two staging sites in 2006, 2007, 2009 and 2010 to investigate whether reverse movements occurred between them. In the four-year period, 63 detected individuals backtracked south from SAO to PV in one or more years. These movements occurred in all years of the study thus demonstrating the annual occurrence of flights of ∼200 km in the opposite direction to the normal northward migration. There was no significant difference in body condition (mass), sex or day of first sighting in SAO between birds that made or did not make reverse movements to PV. However, individuals (N = 11) that backtracked to PV from SAO had significantly lower hematocrit levels at the time of capture than SAO resident birds (N = 205). Because migrating shorebirds have been shown to restore low hematocrit levels before undertaking rapid fuel storage to power long flights, we hypothesise that red knots backtracking to PV were probably behind schedule on migration, and thus may have traded-off the small cost of a ∼200 km flight for the increased foraging time and high quality soft-shell prey available late in the season at PV. This hypothesis helps to explain the later staging phenology of red knots using PV, and its role as an alternative staging area in the northward migration.

Abstract & References : Full Text : PDF (267 KB)

Inferring the Migratory Status of Woodland Birds using Ringing Data: The Case of a Constant-Effort Site Located in the Iberian Highlands Full Access
Iván de la Hera, Jordi Gómez, Teresa Andrés, Pablo González-Ocio, Pablo Salmón, Mikel Salvador, Azaitz Unanue, Francisco Zufiaur and Alejandro Onrubia
pg(s) 77–95


Abstract

Understanding the spatiotemporal distribution of birds is crucial for effective management and conservation of their populations. However, we still have only limited knowledge not only of the wintering destinations of many Iberian breeding migrants but also of aspects as general as the migratory behaviour of the populations of many common avian species that breed in the Iberian highlands. We used bird-ringing data to shed light on the migratory status (migratory, partially-migratory or sedentary) of the breeding populations of 13 common species occurring year-round in a woodland located on an Iberian plateau (Garaio, Araba, Spain; 574 m.a.s.l.), where ringing activities have been carried out over the last 20 years. To assess the extent to which birds breeding on this site remain in the area during winter and/or are replaced by conspecifics coming from other areas, we analysed: (1) changes in relative abundance of birds between summer and winter, (2) the frequency of sedentary individuals (birds captured both in summer and winter period in the study area) in relation to the number of individuals captured only in summer (summer visitors) or in winter (wintering birds), and (3) variation in wing length among summer, wintering and sedentary birds. Our results revealed great variation among species in the intensity of migratory behaviour, and a general arrival of foreign conspecifics during the winter for most of the species studied. Likewise, our study represents an illustrative example of how long-term ringing can be used to shed light on the migratory status of bird populations.

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Habitat Preferences for Territory Selection by the Endangered Eastern Iberian Reed Bunting Emberiza Schoeniclus witherbyi Full Access
Pablo Vera , Eduardo J. Belda, Laura Kvist, S. Ignacio Encabo, Marcial Marín and Juan S. Monrós
pg(s) 97–110


Abstract

Given the 80% decline of the eastern Iberian reed bunting Emberiza schoeniclus witherbyi breeding population in recent decades, our aim was to identify the habitat components selected during territory establishment and to characterise the vegetation features that are positively or negatively selected at the territory scale. GLMM were used to explain the occurrence of territories in 11 wetlands. Fourteen variables with four vegetation dominance categories were analysed with respect to habitat composition, while occupancy of seven vegetation classes and 12 reed structural parameters were analysed with respect to habitat structure. The proportion of reed-cattails (Typha) measured by the habitat approach was the variable with the greatest likelihood of being the model that best fitted our data, but showed poor discriminative ability. The proportion of reed with tussocks was higher in occupied territories than in non-occupied territories. The main results are consistent with a previous study of habitat preference at a wetland scale and seem to be associated both with reduced predation risk and provision of nesting and feeding opportunities. Management guidelines to enhance the presence of the vegetation classes preferred by the species are discussed.


SHORT COMMUNICATIONS

The use of a Low Cost High Speed Camera to Monitor Wingbeat Frequency in Hummingbirds (Trochilidae) Full Access
Ronny Steen
pg(s) 111–120


Abstract
Wingbeat frequency is an important parameter when studying flight performance in hummingbirds and could be put into an ecological and evolutionary context to investigate the decisions that a hummingbird takes regarding foraging efficiency. Previous studies of wingbeat frequencies in hummingbirds have been undertaken with captive birds, most probably due to limitations of experimental design and/or less mobile equipment. In the present paper I describe how I used a budget camera, which captured 220 frames per sec (fps), to film hummingbirds in order to quantify wingbeat frequency under natural conditions in Costa Rica. With this equipment I was able to obtain detailed information about stationary hovering flight in three different species; the charming hummingbird Amazilia decora, purple-throated mountain-gem Lampornis calolaema and violet sabrewing Campylopterus hemileucurus. Wingbeat frequency was higher for the purple-throated mountain-gem and the charming hummingbird compared to the larger violet sabrewing. It did not differ between the purple-throated mountain-gem and the charming hummingbird, which are more similar in size. In the purple-throated mountain-gem I found a higher wingbeat frequency and increased body inclination while hover-feeding compared to hovering in front of the feeder; hence it may be more costly to hover while feeding. It is hoped that the video techniques used here will encourage researchers to record wingbeat frequencies across a range of animal taxa.
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Promiscuous Brown Booby Sula leucogaster Females Perform Reverse Mounting Full Access
Natalia Gañán, Víctor Argáez, Nadia Neri, Natalia Lifshitz and Roxana Torres
pg(s) 121–125


Abstract

Reverse mounting (RM), i.e. where the female mounts the male, has been recorded in some bird species, yet the potential function of this behaviour is not clear. Here, we describe the frequency of RM in the brown booby Sula leucogaster and the behavioural context in which it occurs. We found that 12% (4 out of 33) of focal pairs performed RM. Time spent at the territory and intra-pair courtship and copulations did not differ between RM and non-RM pairs. Females that performed RM were more prone to engage in extra-pair courtship than females that did not perform RM, and male partners of females that performed RM were more likely to engage in extra-pair copulations; however, the probability of laying a clutch did not differ between RM and non-RM pairs. Hence, in the brown booby our data suggest that it is unlikely that RM plays a role during courtship by strengthening pair formation or pair bonds. The potential functional role and the mechanisms modulating RM in promiscuous females need to be further investigated.

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Characteristics of Sand Martin Riparia riparia Colonies in Artificial River Walls Full Access
Jon Etxezarreta and Juan Arizaga
pg(s) 127–134


Abstract

Artificial structures play a significant role as optional breeding places for the sand martin. However, it is virtually unknown which factors determine habitat selection in these artificial sites and to what extent the species selects the same key features that it would in its natural habitat. We compared 16 variables from artificial walls with pipes in channelled rivers between walls holding (N = 56) or not holding (N = 50) a sand martin breeding colony. The presence of colonies was negatively associated with the distance of the breeding wall from the water and positively associated with flooding risk. Bibliographic data were used as a reference for the characteristics of natural breeding habitat. The sand martin selected similar key factors in artificial habitats as when breeding in a natural setting. These factors could probably be linked to limiting predator access to the colony and the occurrence of periodical rinsing episodes that may minimise parasite loads in nesting cavities.

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Haemosporidians in Iberian Bluethroats Luscinia svecica Full Access
M. Ángeles Rojo, Francisco Campos, Tomás Santamaría and M. Ángeles Hernández
pg(s) 135–143


Abstract

Haemosporidian infection (Plasmodium spp., Haemoproteus spp. and Leucocytozoon spp.) was analysed in 101 bluethroats Luscinia svecica captured in the Iberian Central Range during the 2007 and 2008 breeding seasons. Of them, 58.4% were infected with single infections of haemosporidians distributed betweenPlasmodium. spp. (42.9%), Haemoproteus spp. (30.3%) and Leucocytozoon spp. (14.3%). A smaller percentage harboured double infections (12.5%): in these double infections, three birds were found to be infected with Haemoproteus spp.-Haemoproteus spp., two with Haemoproteus spp.-Plasmodium spp. and two withLeucocytozoon spp.-Plasmodium spp. Twentyseven different mitochondrial DNA haplotypes of malaria parasites were found: a) eight belonging to Plasmodiumspp., two of which (P-SGS1 and P-WW3) have previously been recorded in bluethroats in Sweden, and one which has been identified in this study for the first time (P-LSV10); b) thirteen belonging to Haemoproteus spp., four of which (WW2, EMSPO03, RW1 and ARW1) have previously been recorded in birds with migratory habits and nine which are described for the first time in this study (H-LSV01 — H-LSV09); and c) six haplotypes of Leucocytozoon spp., of which one (Leucocytozoon lBT2) has previously been recorded in bluethroats in Sweden and another is described for the first time in this study (L-LSV11). Our results show that body condition did not differ between infected and uninfected birds.

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Leucocyte Levels in Some Antarctic and Non-Antarctic Penguins Full Access
Verónica L. D'amico, Marcelo Bertellotti, Julia I. Díaz, Néstor Coria, Virginia Vidal and Andrés Barbosa
pg(s) 145–152


Abstract

We studied leucocyte levels in several Antarctic and non-Antarctic penguins. A total of 107 blood samples of chinstrap Pygoscelis antarctica, gentoo P. papuaand Adélie P. adeliae penguins at Isla 25 de Mayo/King George Island (South Shetland Islands, Antarctica) and Magellanic penguins Spheniscus magellanicusat Península Valdés (Chubut, Argentina), were collected and analysed during the 2009–2010 breeding season. We observed that chinstrap and Adélie penguins had lower total leucocyte counts than Magellanic and gentoo penguins. We provide some potential explanations for species differences in leucocyte levels.

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Seasonal Space use and Territory Size of Resident Sparrows in the Central Monte Desert, Argentina Full Access
M. Cecilia Sagario and Víctor R. Cueto
pg(s) 153–159


Abstract

Knowledge of space use and territoriality of New World birds largely derives from studies in temperate North America and the tropics, whereas it remains poorly studied in temperate South America, particularly in arid environments. Here we studied the seasonal space use and territory size among resident individuals of three sparrows in a temperate semi-desert of Argentina: the ringed warbling-finch Poospiza torquata, the rufous-collared sparrow Zonotrichia capensis and the manycoloured Chaco-finch Saltatricula multicolor. Both territorial behaviour and use of space of the three species showed seasonal changes. The ringed warbling-finch and the rufous-collared sparrow used larger areas during the non-breeding season than during the breeding season, while the many-coloured Chaco-finch used areas of similar size in the two periods. Defence activities were absent for all three species during the non-breeding season. During the breeding season, each species defended territories that were smaller for the rufous-collared sparrow (0.79 ± 0.04 ha) than for the ringed warbling-finch (1.35 ± 0.04 ha) and the many-coloured Chaco-finch (1.21 ± 0.07 ha). Seasonal territoriality and territory size reported for resident individuals were similar to those reported for north-temperate sparrows in xeric environments.

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Seasonal Shift in the Diet Composition of European Bee-Eaters Merops apiaster at the Northern Edge of Distribution Full Access
Susanne Arbeiter, Hannah Schnepel, Karl Uhlenhaut, Yves Bloege, Martin Schulze and Steffen Hahn
pg(s) 161–170


Abstract

European bee-eaters Merops apiaster forage almost exclusively on airborne insects caught on the wing. The availability of this food might be temporally limited due to adverse weather conditions, especially at climatically sub-optimal breeding sites. We determined seasonal variation in the diet composition in adult and nestling bee-eaters at the species' northernmost breeding colonies by analysing food remains from pellets and by direct observation. Adult bee-eaters preyed on a wide range of insect species with more than 97% belonging to the taxonomic orders Hymenoptera, Odonata and Coleoptera. We observed consistent seasonal changes in adult diet composition from the pre-incubation to the late chick rearing period. The dry mass proportion of dragonflies decreased remarkably in the adult diet as chick rearing started, whereas the consumption of small Hymenopterans increased by the end of the chick provisioning period. Additionally, we found differences in the diet composition of adults and nestlings. The higher amount of bumblebees and dragonflies in the nestling diet was temporally associated with a decrease of these components in the adult diet, indicating that breeding birds preferentially feed larger prey items to their offspring than those that they consume themselves.


FORUM

The 1902 Convention for the Protection of Birds in Historical and Juridical Perspectiveal Full Access
Michael J. Bowman
pg(s) 171–196

 

AbstractRecent contributions to this journal have discussed the impact, actual and potential, of the first significant treaty in the field of avian conservation, the 1902 Paris Convention for the Protection of Birds Useful to Agriculture. This article seeks to expand upon that discussion by providing further information on the nature and development of the international legal system, highlighting in particular the various factors that affect the practical impact that such instruments are likely to exert. It suggests in particular that, in addition to the rigour and suitability of the substantive provisions, it is necessary to consider the effectiveness of the mechanisms established for the treaty's implementation, and the number and identity of the states that can be persuaded to participate, since the importance accorded to state comsovereignty within the international legal order is such that relatively little can be achieved without their individual consent. It has taken many decades of experimentation for treaty negotiators to devise legal instruments that are capable of bringing about significant progress in the conservation field, and the pioneering nature of the 1902 Convention was such that its practical impact was always likely to be limited. Its true significance is therefore primarily historical, serving as a form of stepping stone to the more advanced instruments of the modern era.
Noticiario Ornitológico Full Access
Blas Molina, Javier Prieta y Juan Antonio Lorenzo (Canarias)
pg(s) 197–231
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