Seasonal and diurnal increases in energy stores in migratory warblers at an autumn stopover site along the Asian–Australasian flyway

  • Martha Maria SanderEmail author
  • Wieland Heim
  • Heiko Schmaljohann
Original Article


In contrast to the rapidly growing body of knowledge on migratory routes, wintering grounds and timing of annual life cycle events of migratory birds, knowledge on how migratory songbirds refuel at stopover sites along the Asian–Australasian flyway has increased only slowly, despite the fact that migrant birds show declining trends along it. We analysed the amount and variation of energy stores between species, variation of energy stores within the day and within the season, and estimated flight ranges of ten closely related warbler species (genera Acrocephalus, Arundinax, Locustella and Phylloscopus), captured at a stopover site in the Russian Far East during the autumn migration. We found significant differences in the species’ energy stores, with Pallas’s Leaf Warbler Phylloscopus proregulus having by far the highest. All species increased their energy stores within the day, and eight species increased their energy stores within the season. Individuals with the highest estimated flight ranges were able to cover a distance of 470 km during one nocturnal flight bout, which would have resulted in a minimum of nine stopovers before the birds reached their wintering grounds. We assume that a combination of factors determines the variation in energy stores between these species. We discuss the potential for these birds to exploit different habitats and refuelling strategies according to the distribution of species-specific refuelling habitats, and a variety of food resources, along the migratory route. This study is the first to provide information on energy stores, refuelling strategies and flight ranges for a set of closely related songbird species migrating along the Asian–Australasian flyway.


Refuelling Flight range Songbird East Asia Phylloscopus 


Saisonale und tägliche Energiezunahme bei ziehenden Singvögeln in einem Rastgebiet des Ostasiatischen Zugweges

Der Kenntnisstand zu den Zugwegen, den Winterquartieren und der zeitlichen Organisation des Jahreszyklus ziehender Singvogelarten hat sich in den letzten Jahren stark verbessert. Weitaus weniger ist über die Fettdeposition und die Rastökologie bekannt. Dies gilt insbesondere für Singvogelarten, welche entlang der Ostasiatischen Route in ihre Winterquartiere ziehen. Hier vergleichen wir die Energiereserven von zehn verschiedenen Arten aus den Gattungen Acrocephalus, Arundinax, Locustella und Phylloscopus an einem Zwischenrastplatz im Fernen Osten Russlands während des Herbstzuges. Dabei analysieren wir Unterschiede zwischen den Arten und im Verlauf des Tages und der Saison. Wir konnten signifikante zwischenartliche Unterschiede in den Energiereserven finden, wobei Goldhähnchen-Laubsänger Phylloscopus proregulus die höchsten Reserven aufwiesen. Alle Arten zeigten eine Zunahme im Tagesverlauf, und bei acht Arten konnten wir eine signifikante Zunahme im Laufe der Herbstsaison feststellen. Basierend auf den beobachteten Energiereserven konnten wir maximale Flugreichweiten berechnen, wobei die fettesten Individuen bis zu 470 km in einer Nacht zurücklegen könnten. Damit müssten die Vögel mindestens neun Mal rasten, um ihre Winterquartiere in Südostasien zu erreichen. Wahrscheinlich ist eine Vielzahl von Faktoren für die zwischenartlichen Unterschiede in den Energiereserven relevant. Zum Einen sind die Habitate und die verfügbare Nahrung in unserem Untersuchungsgebiet vermutlich von verschiedener Qualität für verschiedene Arten. Zum anderen könnten die Arten unterschiedliche Zugstrategien aufweisen, je nach Verfügbarkeit des bevorzugten Habitats entlang der Route. Diese Studie ist die erste, welche die Energiereserven und Flugreichweiten einer Gruppe nah verwandter ziehender Singvogelarten im Asiatisch-Australasiatischen Zugwegssystem untersucht.



The authors would like to thank Sergei M. Smirenski and the staff of Muraviovka Park as well as all the volunteers who participated in the bird ringing activities. An earlier version of this manuscript was improved by the comments of Franz Bairlein and Dan Chamberlain and two anonymous reviewers. Our study was carried out in accordance with the legal and ethical requirements for animal research and welfare of the Russian Federation. Birds were captured and marked with permission from the Russian Bird Ringing Centre.


The work of the Amur Bird Project at Muraviovka Park was supported by the Förderkreis Allgemeine Naturkunde (Biologie), the German Ornithologists’ Society, NABU Regionalverband Erzgebirge, the Sound Approach, the Mohamed bin Zayed Species Conservation Fund, the British Ornithologists’ Union, the Oriental Bird Club, ProRing, Rotary Club Potsdam, the Ornithologischer Verein zu Leipzig, Carl Zeiss Sports Optics, as well as private donors and supporters.

Supplementary material

10336_2019_1701_MOESM1_ESM.pdf (143 kb)
Supplementary material 1 (PDF 143 kb)


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Copyright information

© Deutsche Ornithologen-Gesellschaft e.V. 2019

Authors and Affiliations

  1. 1.Dipartimento di Scienze della Vita e Biologia dei SistemiUniversità di TorinoTurinItaly
  2. 2.Institute of Landscape EcologyUniversity of MünsterMünsterGermany
  3. 3.Institute of Avian Research “Vogelwarte Helgoland”WilhelmshavenGermany
  4. 4.Institute for Biology und Environmental Sciences (IBU)Carl von Ossietzky University of OldenburgOldenburgGermany

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