Autumn Migration Strategies and Trapping Numbers in the Common Ringed Plover Charadrius hiaticula in Southern Sweden

Ardea

Anders Hedenström¹  Linus Hedh² 

[1] 1 Department of Biology, Ecology Building, Lund University, SE-223 62 Lund, Sweden; 2Ottenby Bird Observatory, PL. 1500, SE-380 65 Degerhamn, Sweden;1 Department of Biology, Ecology Building, Lund University, SE-223 62 Lund, Sweden;

关键词: Fuel Loads;   

DOI  :  

学科分类：动物科学

来源: Nederlandse Ornithologische Unie/Netherlands Ornithological Union

【 摘 要 】

InthisstudywecompareautumnmigrationstrategiesintwosubspeciesoftheCommonRingedPloverCharadriushiaticulainthesouthernBalticSea.Thisspeciesexhibitsaleap-frogmigrationpattern,wherebynortherlybreedingpopulations(C.h.tundrae;henceforthtundrae)migratepastthewholerangeofthesouthernpopulation(C.h.hiaticula;henceforthhiaticula).Hiaticulamigratestheshortestdistanceandishypothesisedtominimizeenergyspentonmigration,whereastundraeishypothesizedtominimizetime,becausealongermigrationimposestimeconstraintsuponotherstagesofamigrant'slifehistory,suchasmoultandbreeding.WeusebiometricdatacollectedatOttenbyBirdObservatory,southernÖland,Sweden,between1946–2012,totestwhethereachsubspeciesdemonstratescharacteristicsassociatedwitheitheranenergy-ortime-minimizedmigration.Weusedthedeclineinwingandtotal-headlengthovertheseasontodistinguishthesubspecies.Hiaticulamigratedearlierintheseason(July—midAugust)comparedtotundrae(lateJuly—lateSeptember).Alsotherelativetimingofagegroupsbetweenthetwosubspeciesdiffered.Juvenileandadulthiaticulamigratedsynchronizedintime,whereastundraehadtwomainperiodsofpassageforadults(earlier)andjuveniles(later).ThetimingfitsthatofotherstudiesandgivescomplementaryinformationaboutthepassageinEurope.Juveniletundraeshowedapositivetrendofobservedfuelloadsastheseasonprogressed,whereastheothergroupsdidnot.DailyfuellingrateswithinthesameseasonwerelowcomparedtootherwaderspeciesthatuseOttenbyasastopoverandnodifferencebetweensubspecieswasfound.However,tundraestoppedoverforashortertimecomparedwithhiaticula.Therewasnodifferenceinaveragemigrationspeedbetweenthesubspecies,althoughtundraehadahighermaximumspeed.Therewaslargevariationinyearlynumbersbetweenageclassesinthetwosubspecies.Inhiaticulatheyearlyaveragewas8adultsand37juveniles.Theratioofjuveniletoadulttundraeontheotherhandwasalmost1:1,indicatingequaluseofOttenbyasstopoversiteinautumn.Notrendsinobservedfuelloadsovertheseasoninhiaticulaareconsistentwithanenergyminimizingmigration.Asfortundrae,ashorterstopovertimecomparedtohiaticulaandapositiverelationshipbetweenobservedfuelloadandtime,areconsistentwithtimeminimizingmigration.However,therearemanyuncertaintiesandmorestudiesofmigratorybehavioursatseveralsitesalongthemigrationrouteareneededtounderstandthedifferencesinmigrationstrategiesinthisspecies.

【 授权许可】

Unknown