liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Emlen funnel experiments revisited: methods update for studying compass orientation in songbirds
Lund University, Sweden.
Lund University, Sweden; Bulgarian Academic Science, Bulgaria.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
Show others and affiliations
2016 (English)In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, no 19, 6930-6942 p.Article in journal (Refereed) Published
Abstract [en]

1 Migratory songbirds carry an inherited capacity to migrate several thousand kilometers each year crossing continental landmasses and barriers between distant breeding sites and wintering areas. How individual songbirds manage with extreme precision to find their way is still largely unknown. The functional characteristics of biological compasses used by songbird migrants has mainly been investigated by recording the birds directed migratory activity in circular cages, so-called Emlen funnels. This method is 50 years old and has not received major updates over the past decades. The aim of this work was to compare the results from newly developed digital methods with the established manual methods to evaluate songbird migratory activity and orientation in circular cages. 2 We performed orientation experiments using the European robin (Erithacus rubecula) using modified Emlen funnels equipped with thermal paper and simultaneously recorded the songbird movements from above. We evaluated and compared the results obtained with five different methods. Two methods have been commonly used in songbirds orientation experiments; the other three methods were developed for this study and were based either on evaluation of the thermal paper using automated image analysis, or on the analysis of videos recorded during the experiment. 3 The methods used to evaluate scratches produced by the claws of birds on the thermal papers presented some differences compared with the video analyses. These differences were caused mainly by differences in scatter, as any movement of the bird along the sloping walls of the funnel was recorded on the thermal paper, whereas video evaluations allowed us to detect single takeoff attempts by the birds and to consider only this behavior in the orientation analyses. Using computer vision, we were also able to identify and separately evaluate different behaviors that were impossible to record by the thermal paper. 4 The traditional Emlen funnel is still the most used method to investigate compass orientation in songbirds under controlled conditions. However, new numerical image analysis techniques provide a much higher level of detail of songbirds migratory behavior and will provide an increasing number of possibilities to evaluate and quantify specific behaviors as new algorithms will be developed.

Place, publisher, year, edition, pages
WILEY-BLACKWELL , 2016. Vol. 6, no 19, 6930-6942 p.
Keyword [en]
Computer vision; image analysis; magnetic alignment; navigation
National Category
Zoology
Identifiers
URN: urn:nbn:se:liu:diva-132525DOI: 10.1002/ece3.2383ISI: 000385626100014OAI: oai:DiVA.org:liu-132525DiVA: diva2:1046409
Note

Funding Agencies|Centre for Animal Movement Research (CAnMove) - Linnaeus grant from Swedish Research Council [349-2007-8690]; Lund University; Royal Swedish Physiographical Society; Swedish Research Council [621-2013-4361]; VR project VIDI [2012-4321]; Vinnova Industry Excellence Center LINK-SIC

Available from: 2016-11-14 Created: 2016-11-13 Last updated: 2016-12-02

Open Access in DiVA

fulltext(2182 kB)9 downloads
File information
File name FULLTEXT01.pdfFile size 2182 kBChecksum SHA-512
bef0782d710c2c64d9b972858aff7e771361db46e92fa44c99c9b6ef76c0f5c74fe48fc0422bd211f23627d5fc584fd37ba38a2ac7eecda8978e449607a28735
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Veibäck, ClasÖfjäll, KristofferHendeby, GustafFelsberg, MichaelGustafsson, Fredrik
By organisation
Automatic ControlFaculty of Science & EngineeringComputer VisionCenter for Medical Image Science and Visualization (CMIV)
In the same journal
Ecology and Evolution
Zoology

Search outside of DiVA

GoogleGoogle Scholar
Total: 9 downloads
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

Altmetric score

Total: 32 hits
ReferencesLink to record
Permanent link

Direct link