Change search
ReferencesLink to record
Permanent link

Direct link
No compensatory fuelling due to late autumn migration in the Garden Warbler Sylvia borin
Stockholm University, Faculty of Science, Department of Zoology, Ethology.ORCID iD: 0000-0002-9741-4431
Stockholm University, Faculty of Science, Department of Zoology, Ethology.
Stockholm University, Faculty of Science, Department of Zoology, Ethology.
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Birds migrating late in the migration season may need to compensate for the late departure by increasing migration speed. To increase migration speed late migrants should depart from stopovers along the route with larger fuel loads than early migrants. Both higher migration speeds and increasing fuel loads with the progress of the season have been reported in the literature. Here we test if Garden Warblers (Sylvia borin) show different fuelling strategies when captured on migration in the early or late part of autumn migration and given unlimited access to food. We also included a group of birds that were captured early in the season but held under a light regime with shorter day lengths to simulate thirty days advancement in time. We found no difference in maximum body mass between the groups and all groups reached fairly large fuel loads (mean: 39.2 % of lean body mass). Maximum fuel load was also strongly correlated with fuel deposition rate and this may suggest that Garden Warblers migrate at high speed during the entire season, which leaves little room for increasing speed later in the season.

National Category
Behavioral Sciences Biology
Research subject
Ethology
Identifiers
URN: urn:nbn:se:su:diva-126968OAI: oai:DiVA.org:su-126968DiVA: diva2:904547
Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2016-02-22Bibliographically approved
In thesis
1. Migratory routes and stopover behaviour in avian migration
Open this publication in new window or tab >>Migratory routes and stopover behaviour in avian migration
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Migratory birds, some small and light weight as matchboxes, engage in seasonal inter-continental journeys in order to take advantage of the long summer days and abundance of food at northern latitudes to breed and raise their young, and then escape the harsh winters by migrating to lower latitudes. This thesis deals with two important aspects of migration, the routes taken during migration and the birds’ behaviour at stopovers. The migratory routes are for many species unknown, whole or in part, and this is especially true for species that migrate nocturnally. At stopovers birds replenish fuel reserves that powers migratory flight, and studying how birds utilise stopovers is important in order to understand how migration is organised. In this thesis I have used modern tracking technology to study both continental wide movements of thrush nightingales (Luscinia luscinia) and common rosefinches (Carpodacus erythrinus) using small light-level geolocators, and smaller scale movements at a single stopover site of garden warblers (Sylvia borin) using miniature radio-transmitters. I have also studied the fuelling behaviour of garden warblers during autumn migration in the field and in the lab, and great reed warblers (Acrocephalus arundinaceus) at a stopover site on Crete during spring migration after the Sahara crossing. The thesis discusses the significance of several aspects of migration shown by the birds that would have been very difficult to detect without the aid of modern tracking technology, such as loop migration, prolonged stops during migration, multiple wintering sites, and nocturnal relocations at stopover sites. Studies carried out at stopover sites also show that garden warblers and great reed warblers can attain large fuel loads even at sites where they have no barrier to cross and this might be a result of good foraging conditions. The thesis also highlights the importance of combining different techniques when studying stopover behaviour to get reliable estimates on stopover durations and fuel deposition rates as well as the importance of choosing sites preferred by birds when planning stopover studies.

Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University, 2016. 49 p.
Keyword
Bird migration, migration routes, stopover, geolocator, radio telemetry, tracking, fuel deposition
National Category
Behavioral Sciences Biology
Research subject
Ethology
Identifiers
urn:nbn:se:su:diva-126975 (URN)978-91-7649-333-5 (ISBN)
Public defence
2016-04-08, Vivi Täckholmsalen (Q-salen), NPQ-huset, Svante Arrhenius väg 20, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript.

Available from: 2016-03-18 Created: 2016-02-18 Last updated: 2016-03-18Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Stach, RobertJakobsson, SvenKullberg, Cecilia
By organisation
Ethology
Behavioral Sciences Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 49 hits
ReferencesLink to record
Permanent link

Direct link