Nest Site Selection and Breeding Success in an Expanding Species, the Cattle Egret Bubulcus ibis
[摘要] NativetotheIndo-Africanarea,theCattleEgretBubulcusibisisnowacosmopolitanspecies,stillingreatrangeexpansion.Thefactorsaffectingbreedingsuccessofthespeciesremainhoweverpoorlyknown,andhereweinvestigatethebreedingbiologyoftheCattleEgretinanewbreedingpopulationintheSoummamValley(PetiteKabylie,Algeria).Theinstallationchronologyandnestsiteselectionaredescribed,andtheireffectonbreedingsuccessinvestigated.ThenestingseasonlastedgenerallyfromtheendofMarchtotheendofJuly.Clutchsize,numberofhatchedchicksandbreedingsuccesswerelowcomparedtootherbreedingareasintheMediterranean.ThefirstCattleEgretsarrivingatthecolonyinMarchselectedthehighesttreesandthehighestnestsupportsclosetothetrunk.Withnewarrivalsduringthecourseoftheseason,agradualdecreasewasobservedintheheightofthenestswhichwereprogressivelybuiltawayfromthetrunk.Thisselectivebehaviourallowedthefirstinstalledpairstohaveabetterbreedingsuccess.Thisphenomenonisdiscussedherewithintheframeworkofterritorialityandthebreedingadvantagesofbeinghighrankinginthe‘territorialhierarchy’fortheindividual.
[发布日期] [发布机构]
[效力级别] [学科分类] 动物科学
[关键词] North Africa [时效性]
