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Karwinkel T, Peter A, Holland RA, Thorup K, Bairlein F, Schmaljohann H. A conceptual framework on the role of magnetic cues in songbird migration ecology. Biol Rev Camb Philos Soc 2024; 99:1576-1593. [PMID: 38629349 DOI: 10.1111/brv.13082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 03/27/2024] [Accepted: 03/29/2024] [Indexed: 07/06/2024]
Abstract
Migrating animals perform astonishing seasonal movements by orienting and navigating over thousands of kilometres with great precision. Many migratory species use cues from the sun, stars, landmarks, olfaction and the Earth's magnetic field for this task. Among vertebrates, songbirds are the most studied taxon in magnetic-cue-related research. Despite multiple studies, we still lack a clear understanding of when, where and how magnetic cues affect the decision-making process of birds and hence, their realised migratory behaviour in the wild. This understanding is especially important to interpret the results of laboratory experiments in an ecologically appropriate way. In this review, we summarise the current findings about the role of magnetic cues for migratory decisions in songbirds. First, we review the methodological principles for orientation and navigation research, specifically by comparing experiments on caged birds with experiments on free-flying birds. While cage experiments can show the sensory abilities of birds, studies with free-flying birds can characterise the ecological roles of magnetic cues. Second, we review the migratory stages, from stopover to endurance flight, in which songbirds use magnetic cues for their migratory decisions and incorporate this into a novel conceptual framework. While we lack studies examining whether and when magnetic cues affect orientation or navigation decisions during flight, the role of magnetic cues during stopover is relatively well studied, but mostly in the laboratory. Notably, many such studies have produced contradictory results so that understanding the biological importance of magnetic cues for decisions in free-flying songbirds is not straightforward. One potential explanation is that reproducibility of magnetic-cue experiments is low, probably because variability in the behavioural responses of birds among experiments is high. We are convinced that parts of this variability can be explained by species-specific and context-dependent reactions of birds to the study conditions and by the bird's high flexibility in whether they include magnetic cues in a decision or not. Ultimately, this review should help researchers in the challenging field of magnetoreception to design experiments meticulously and interpret results of such studies carefully by considering the migration ecology of their focal species.
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Affiliation(s)
- Thiemo Karwinkel
- Institute of Avian Research 'Vogelwarte Helgoland', An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
- Carl von Ossietzky Universität Oldenburg, School of Mathematics and Science, Institute of Biology and Environmental Sciences, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Annika Peter
- Carl von Ossietzky Universität Oldenburg, School of Mathematics and Science, Institute of Biology and Environmental Sciences, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Richard A Holland
- School of Environmental and Natural Sciences, Bangor University, Bangor, LL57 2UW, UK
| | - Kasper Thorup
- Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen, Denmark
| | - Franz Bairlein
- Institute of Avian Research 'Vogelwarte Helgoland', An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
- Max Planck Institute of Animal Behavior, Am Obstberg 1, Radolfzell, 78315, Germany
| | - Heiko Schmaljohann
- Institute of Avian Research 'Vogelwarte Helgoland', An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
- Carl von Ossietzky Universität Oldenburg, School of Mathematics and Science, Institute of Biology and Environmental Sciences, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
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2
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Pearman WS, Duffy GA, Gemmell NJ, Morales SE, Fraser CI. Long-distance movement dynamics shape host microbiome richness and turnover. FEMS Microbiol Ecol 2024; 100:fiae089. [PMID: 38857884 PMCID: PMC11212666 DOI: 10.1093/femsec/fiae089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 05/22/2024] [Accepted: 06/08/2024] [Indexed: 06/12/2024] Open
Abstract
Host-associated microbial communities are shaped by host migratory movements. These movements can have contrasting impacts on microbiota, and understanding such patterns can provide insight into the ecological processes that contribute to community diversity. Furthermore, long-distance movements to new environments are anticipated to occur with increasing frequency due to host distribution shifts resulting from climate change. Understanding how hosts transport their microbiota with them could be of importance when examining biological invasions. Although microbial community shifts are well-documented, the underlying mechanisms that lead to the restructuring of these communities remain relatively unexplored. Using literature and ecological simulations, we develop a framework to elucidate the major factors that lead to community change. We group host movements into two types-regular (repeated/cyclical migratory movements, as found in many birds and mammals) and irregular (stochastic/infrequent movements that do not occur on a cyclical basis, as found in many insects and plants). Ecological simulations and prior research suggest that movement type and frequency, alongside environmental exposure (e.g. internal/external microbiota) are key considerations for understanding movement-associated community changes. From our framework, we derive a series of testable hypotheses, and suggest means to test them, to facilitate future research into host movement and microbial community dynamics.
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Affiliation(s)
- William S Pearman
- Department of Marine Science, University of Otago, 310 Castle St, Dunedin 9016, New Zealand
- Department of Anatomy, School of Biomedical Sciences, University of Otago, 270 Great King Street, Dunedin 9016, New Zealand
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, 720 Cumberland St, Dunedin 9016, New Zealand
| | - Grant A Duffy
- Department of Marine Science, University of Otago, 310 Castle St, Dunedin 9016, New Zealand
| | - Neil J Gemmell
- Department of Anatomy, School of Biomedical Sciences, University of Otago, 270 Great King Street, Dunedin 9016, New Zealand
| | - Sergio E Morales
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, 720 Cumberland St, Dunedin 9016, New Zealand
| | - Ceridwen I Fraser
- Department of Marine Science, University of Otago, 310 Castle St, Dunedin 9016, New Zealand
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3
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Shochat E, Nilsson C, Lisovski S, Chernetsov N. Editorial: Optimal bird migration: Implications for navigation, physiology, and stopover ecology. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1029958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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4
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López-Iborra GM, Bañuls A, Castany J, Escandell R, Sallent Á, Suárez M. Drivers of migrant passerine composition at stopover islands in the western Mediterranean. Sci Rep 2022; 12:2943. [PMID: 35190639 PMCID: PMC8861067 DOI: 10.1038/s41598-022-06912-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 02/07/2022] [Indexed: 11/28/2022] Open
Abstract
Clues used by migrant birds to select sites for stopover are much less known than their reasons for leaving. Habitat characteristics and geographical location may affect the decision to use an island as a stopover site in different ways for different species. Thus, abundance and composition of migrants may be expected to differ between islands. Using standardized ringing from 9 western Mediterranean islands we evaluate drivers of abundance of trans-Saharan migrant passerines, specifically the role of species continental abundance, island characteristics and geographical location. Although continental abundance is a main driver of migrant composition on all islands migrant composition differs between them. Redundancy analysis and species response models revealed that the main drivers were distance to the nearest land toward the south, which has a positive effect on the number of migrants of most species, and island area, which appears as an important cue used for selecting a stopover island. Species whose abundance is positively related to island area have more pointed wings while species affected by distance to land toward the south have relatively more rounded wings. This suggests a hypothesis on the mechanism that may generate differences in passerine migrant composition between islands based on better efficiency of more pointed wings for long-distance flight.
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Affiliation(s)
- Germán M López-Iborra
- Departamento de Ecología/IMEM Ramon Margalef, Universidad de Alicante, Alicante, Spain.
| | | | | | - Raül Escandell
- Societat Ornitològica de Menorca, Ap. de correus 83, 07720, Es Castell, Spain
| | - Ángel Sallent
- Asociación de Naturalistas del Sureste, Murcia, Spain
| | - Manuel Suárez
- Grup Balear d'Ornitologia i Defensa de La Naturalesa (GOB), Palma de Mallorca, Spain
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5
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Hidalgo-Rodríguez P, Sáez-Gómez P, Blas J, Hedenström A, Camacho C. Body mass dynamics of migratory nightjars are explained by individual turnover and fueling. Behav Ecol 2021. [DOI: 10.1093/beheco/arab042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Body mass is a commonly used indicator of the energy stores of migratory animals and there is considerable evidence that it is a critical determinant of migration decisions and outcomes. Mean population mass often increases during the post-breeding period in most migratory species. Usually, this increase is interpreted as the result of fuel accumulation for migration based on the assumption that mean population mass mirrors mean individual mass. However, an empirical test of this assumption is lacking, and it is unknown whether the general increase in mean population mass is entirely the result of within-individual mass gain, or if it rather reflects a change in the nature of individuals in the population (mass-dependent turnover). We investigated changes in body mass during the post-fledging period of a migratory bird, the Red-necked Nightjar (Caprimulgus ruficollis), and combined longitudinal and cross-sectional data collected over 9 years to disentangle the relative contribution of individual-level (mass gain) and population-level (selective appearance and disappearance) processes. We found that the average body mass of fully-developed juveniles increased as the season progressed and that both individual mass gain and the selective disappearance of lighter individuals contributed to this increase. Contrary to the general expectations for migrants, the turnover of individuals contributed 3.5 times more to the seasonal increase in average body mass than individual mass gain. On a practical note, this differential contribution implied a discrepancy of over 40% between the time-average rates of mass gain (fuel deposition rates) estimated from population-level and individual-level data. Our study calls for caution in the use of population-level changes in body mass to make inferences about individual fuel deposition rates and, more generally, indicates that longitudinal and cross-sectional approaches need to be combined to uncover phenotype-time correlations in natural populations.
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Affiliation(s)
- Paula Hidalgo-Rodríguez
- Department of Molecular Biology and Biochemical Engineering, University Pablo de Olavide, Carretera Utrera km.1, 41013 Seville, Spain
| | - Pedro Sáez-Gómez
- Instituto Multidisciplinar para el Estudio del Medio “Ramon Margalef”, Universidad de Alicante, 03080, Alicante, Spain
- Department of Integrative Sciences, University of Huelva, Campus Universitario El Carmen, Av. Andalucía, 21071 Huelva, Spain
| | - Julio Blas
- Department of Conservation Biology, Estación Biológica de Doñana – CSIC, Av. Américo Vespucio, 26, 41092, Seville, Spain
| | - Anders Hedenström
- Department of Biology, Centre for Animal Movement Research (CAnMove), Lund University, Ecology Building, Sölvegatan 37, 223 62 Lund, Sweden
| | - Carlos Camacho
- Department of Biology, Centre for Animal Movement Research (CAnMove), Lund University, Ecology Building, Sölvegatan 37, 223 62 Lund, Sweden
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Vanni L, Cerritelli G, Turchi A, Giunchi D. Migratory restlessness and stopover duration in Wood sandpiper Tringa glareola. ETHOL ECOL EVOL 2021. [DOI: 10.1080/03949370.2021.1878282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Lorenzo Vanni
- Department of Biology, University of Pisa, Via A. Volta 6, Pisa 56126, Italy
| | - Giulia Cerritelli
- Department of Biology, University of Pisa, Via A. Volta 6, Pisa 56126, Italy
| | - Alessandro Turchi
- Department of Biology, University of Pisa, Via A. Volta 6, Pisa 56126, Italy
| | - Dimitri Giunchi
- Department of Biology, University of Pisa, Via A. Volta 6, Pisa 56126, Italy
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Davis TJ, Keppel G. Fine‐scale environmental heterogeneity and conservation management: Beach‐cast wrack creates microhabitats for thermoregulation in shorebirds. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13865] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
| | - Gunnar Keppel
- UniSA STEMUniversity of South Australia Adelaide SA Australia
- Future Industries Institute University of South Australia Adelaide SA Australia
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Hegyi G, Laczi M, Kötél D, Csörgő T. Melanin-based ornament darkness positively correlates with across-season nutritional condition. Ecol Evol 2020; 10:13087-13094. [PMID: 33304519 PMCID: PMC7713921 DOI: 10.1002/ece3.6898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 11/09/2022] Open
Abstract
Sexually dimorphic ornamental traits are widely regarded as indicators of nutritional condition. However, variation of nutritional condition outside the reproductive and the ornament production seasons has rarely been considered, although it affects the generality of information content, especially for ornaments that may be used across the year. We measured several indicators of migratory and molt condition in male and female blackcaps (Sylvia atricapilla) during their autumn migration, and quantified their crown reflectance. We detected robust correlations between migratory and molt condition indices, and the correlation structure was similar in the two sexes. Furthermore, the across-season measure of body condition was positively related to the darkness of the black crown in males, while being unrelated to reflectance traits of the reddish crown in females. Our results reinforce the possibility that some melanin-based ornaments may be year-round indicators of individual quality via their dependence on nutritional condition.
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Affiliation(s)
- Gergely Hegyi
- Department of Systematic Zoology and EcologyELTE Eötvös Loránd UniversityBudapestHungary
| | - Miklós Laczi
- Department of Systematic Zoology and EcologyELTE Eötvös Loránd UniversityBudapestHungary
| | - Dóra Kötél
- Department of Systematic Zoology and EcologyELTE Eötvös Loránd UniversityBudapestHungary
| | - Tibor Csörgő
- Department of Anatomy, Cell and Developmental BiologyELTE Eötvös Loránd UniversityBudapestHungary
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9
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Ferretti A, Maggini I, Cardinale M, Fusani L. Heat loss in sleeping garden warblers (Sylvia borin) during migration. J Therm Biol 2020; 94:102772. [PMID: 33293004 DOI: 10.1016/j.jtherbio.2020.102772] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 10/06/2020] [Accepted: 10/20/2020] [Indexed: 01/27/2023]
Abstract
For small songbirds, energy is often a limiting factor during migration and, for this reason, they are forced to alternate nocturnal flights with stopovers to rest and replenish energy stores. Stopover duration has a key role for a successful migration and may have an important impact on fitness. Thus, migrants need to optimize their energy consumption at this stage to reduce their permanence at the site. A recent study has shown that lean individuals reduce their metabolic rate when tucking the head in the feathers during sleep. The underlying mechanism is very likely a reduction in conductance, but the thermoregulatory benefit of the increased insulation has never been quantified yet. Here, we compared heat loss in individual migratory birds while sleeping in different postures. Using a thermal camera and a within-individual approach, we estimated that Garden Warblers can reduce their rate of heat loss by 54% by sleeping with the head tucked in the feathers. This energy saving has a relevant impact on the individual's energy balance because it can account for up to 8.69% of daily energy expenditure during stopover. Our study provides novel and important information to understand the fundamental role of thermoregulatory strategies on bird's energy management.
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Affiliation(s)
- Andrea Ferretti
- University of Vienna, Department of Behavioural and Cognitive Biology, Althanstr. 14, 1090 Vienna, Austria; University of Veterinary Medicine, Vienna, Konrad Lorenz Institute of Ethology, Savoyenstr. 1, 1160, Vienna, Austria.
| | - Ivan Maggini
- University of Veterinary Medicine, Vienna, Konrad Lorenz Institute of Ethology, Savoyenstr. 1, 1160, Vienna, Austria.
| | - Massimiliano Cardinale
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Marine Research Institute, 45330 Lysekil, Sweden.
| | - Leonida Fusani
- University of Vienna, Department of Behavioural and Cognitive Biology, Althanstr. 14, 1090 Vienna, Austria; University of Veterinary Medicine, Vienna, Konrad Lorenz Institute of Ethology, Savoyenstr. 1, 1160, Vienna, Austria.
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Klinner T, Schmaljohann H. Temperature change is an important departure cue in nocturnal migrants: controlled experiments with wild-caught birds in a proof-of-concept study. Proc Biol Sci 2020; 287:20201650. [PMID: 33023413 DOI: 10.1098/rspb.2020.1650] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The decision-making process of migrating birds at stopover sites is a complex interplay of the innate migration program and both intrinsic and extrinsic factors. While it is well studied how variation in precipitation, wind and air pressure influence this process, there is less evidence of the effects of temperature changes on the departure decision. Thus, we lack knowledge on how the predicted changes due to global climate change in temperature alone may affect the decision-making process during migration. Aiming to fill parts of this gap, we conducted a proof-of-concept study by manipulating the ambient temperature of temporarily confined wild-caught migrant songbirds under constant feeding conditions. In spring, departure probability increased with a 20°C rise in temperature for both a medium-distance migrant (European robin, Erithacus rubecula) and a long-distance migrant (northern wheatear, Oenanthe oenanthe), and in autumn, departure probabilities of the long-distance migrant both decreased with a 20°C rise and increased with a 20°C drop. Consequently, the temperature is an important departure cue influencing the decision-making process of migrating songbirds. Incorporating causal relationships between changes in temperature and departure probability in migration models could substantially improve our ability to predict the effects of climate change on the phenology of migratory birds.
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Affiliation(s)
- Thomas Klinner
- Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany
| | - Heiko Schmaljohann
- Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany.,Institute for Biology and Environmental Sciences (IBU), Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
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11
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Schmaljohann H, Klinner T. A quasi-experimental approach using telemetry to assess migration-strategy-specific differences in the decision-making processes at stopover. BMC Ecol 2020; 20:36. [PMID: 32641125 PMCID: PMC7346510 DOI: 10.1186/s12898-020-00307-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/30/2020] [Indexed: 12/03/2022] Open
Abstract
Background Migrant birds travel between their breeding areas and wintering grounds by alternating energetically and physiologically demanding flights with periods of rest and fuelling, so-called stopovers. An important intrinsic factor influencing the decision to resume migration is the amount of energy stores available for the next flight. Correlative studies with free-flying birds and experimental studies with caged birds have shown that the amount of energy stores affects the day-to-day, within-day and the directional decision of departure. The methodological advantages of both the correlative and experimental approach are combined when radio-tagging many individuals on the same day and subsequently determining the departure decisions at a high spatiotemporal resolution. Making use of such a quasi-experimental approach with an automated radio-tracking system at stopover, we studied the effect of energy stores on departure decisions and whether they vary between species of different migration strategies experiencing contrasting time constraints. For this, we chose a long-distance migrant, the common redstart (Phoenicurus phoenicurus), and a medium-distance migrant, the European robin (Erithacus rubecula), because the former has to travel at relatively higher speed to reach its wintering ground in a reasonable time at the expense of relatively higher energetic costs for travelling than the latter. Results Common redstarts with higher energy stores were more likely to resume migration than their conspecifics with lower energy stores, whereas this pattern was absent in the European robins. The amount of energy stores significantly affected the timing of departure within the day, with large energy stores yielding early departures in both species. Departure directions from the stopover site during the first night after capture were oriented towards the seasonally appropriate direction but were not affected by variation in energy stores. Conclusions We demonstrate the importance of variation in energy stores on the departure decisions and that it may affect species with different migration strategies dissimilarly in autumn. Nevertheless, knowledge of other intrinsic factors, such as feeding conditions, health status and physiological consequences of previous flights, is additionally required to better understand the departure decisions of migrants, as this is the key to providing an overall assessment of the decision-making process.
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Affiliation(s)
- Heiko Schmaljohann
- Institute for Biology und Environmental Sciences (IBU), Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany. .,Institute of Avian Research, An der Vogelwarte 21, 26386, Wilhelmshaven, Germany.
| | - Thomas Klinner
- Institute of Avian Research, An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
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Stępniewska K, Ożarowska A, Busse P, Bobrek R, Zehtindjiev P, Ilieva M, Meissner W. Autumn migration strategy of juvenile great reed warblers Acrocephalus arundinaceus on the eastern European flyway: a spatiotemporal pattern of accumulation and utilisation of energy stores. THE EUROPEAN ZOOLOGICAL JOURNAL 2020. [DOI: 10.1080/24750263.2020.1814882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- K. Stępniewska
- Avian Ecophysiology Unit, Department of Vertebrate Ecology and Zoology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
- Bird Migration Research Station, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - A. Ożarowska
- Avian Ecophysiology Unit, Department of Vertebrate Ecology and Zoology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - P. Busse
- Bird Migration Research Foundation, Choczewo, Poland
| | - R. Bobrek
- Rakutowskie Bird Ringing Station, Students Naturalists Association of the Jagiellonian University, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - P. Zehtindjiev
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - M. Ilieva
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - W. Meissner
- Avian Ecophysiology Unit, Department of Vertebrate Ecology and Zoology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
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