Wide ranging stopover movements and substantial fuelling in first year garden warblers at a northern stopover site
2015 (English)In: Journal of Avian Biology, ISSN 0908-8857, E-ISSN 1600-048X, Vol. 46, no 3, 315-322 p.Article in journal (Refereed) Published
Migratory birds use stopovers to replenish their fuel reserves and they generally spend more time at stopover sites than theydo in actual fl ight. When arriving at a new stopover site birds may need to search extensively to fi nd a suitable feeding areaand this search and settling period may aff ect the duration of stopover. Stopover behaviour can thus have profound eff ectson the migratory programme and studies on stopover behaviour are important to understand migratory strategies. Wefollowed 51 fi rst-year garden warblers Sylvia borin with radio-transmitters at an autumn stopover site on the island ofGotland in southern Sweden. Our aim was to determine the distance birds relocated from the coastal capture site whensearching for an area to settle in, and also to establish the duration of stopover and put it in relation to refuelling rate byrecapturing a subset of the radio-tracked individuals. Sixteen birds made an extended stopover ( 2 d), relocated inlandfrom the capture site and settled on average 5.6 km from the capture site, with the longest recorded relocation being fourteenkilometres. Birds that relocated nocturnally settled in areas further away than birds that relocated diurnally. Th irteenbirds that continued migration after a short stop carried larger fuel stores than birds that stopped over longer and theyremained close to the capture site until departure. Th ree birds were re-trapped and showed high fuelling rates, between0.3 and 1.1 g d 1 . Th ey left the stopover site with fuel loads between 40 – 56 percent of lean body mass, which possiblywould have allowed them to reach the Mediterranean area without additional refuelling stops.
Place, publisher, year, edition, pages
2015. Vol. 46, no 3, 315-322 p.
Behavioral Sciences Biology
Research subject Ethology
IdentifiersURN: urn:nbn:se:su:diva-115963DOI: 10.1111/jav.00492ISI: 000355622400011OAI: oai:DiVA.org:su-115963DiVA: diva2:801155