African Penguins Spheniscus demersus, Bait Balls and the Allee Effect
[摘要] Wereportco-operativegroupforagingintheAfricanPenguinSpheniscusdemersus.Groupsofapproximately25–165AfricanPenguinswereobservedcirclingschoolsofpelagicfish,sometimesforcingthemtothesurface.Duringthisbehaviour66–75%ofpenguinswereunderwateratanygiventime.SmallernumbersofAfricanPenguinsalsojoinedforaginggroupsofCapeGannetsMoruscapensisandCapeCormorantsPhalacrocoraxcapensis,butdidnotappeartocorralfishschoolswhenoutnumberedbythesespecies.AfricanPenguinsarelistedasEndangeredduetoongoingrapidpopulationdecreases.IfgroupforagingconfersanadvantagetoAfricanPenguins,theirdwindlingpopulationsmaysufferfromanAlleeeffectascoloniesbecometoosmalltosupportsufficientdensitiesofbirdsforforaginggroupstoform.
[发布日期] [发布机构]
[效力级别] [学科分类] 动物科学
[关键词] Predation [时效性]
