Nest Site and Food Composition of the Eagle Owl Bubo bubo in Mongolia

[摘要] Weexamined11EagleOwlBubobubonestsinMongoliaduring2004–06.Fivenestswerelocatedincliffs,threeinrockcolumns,twoinsandyprecipicesandoneonarockledge.Meanheight(aboveground)ofthenestsitestructurewas7.6(SD5.9)mandheightofnestentrancewas3.1(SD2.5)m.Meanclutchsizewas1.7(SD0.9)andthenumberoffledglingswas1.5(SD0.5).Neststructureorentranceheightdidnotcorrelatewiththenumberofeggslaid(r=0.1,r=0.4)oryoungfledged(r=0.001,r=0.1).Weidentified276preyfrompelletsandremainsfromnestsornearbyperches.Pelletsaveraged63.5(SD14.2)by22.2(SD4.1)mmandweighed10.6(SD4.6)gwhencollected.Seventeenspeciesofbirdsweretakenasprey,andrepresented32.2%ofpreybiomass(26.1%byfrequency),while13mammalspeciesconstituted67.8%ofthebiomass(72.2%byfrequency).ThemostfrequentavianpreywastheEurasianSparrowhawkAccipiternisus;themostfrequentmammalianpreywastheMongolianFive-toedJerboaAllactagasibirica.Amphibiansandbeetlestogetherrepresentedaverysmallpercentage(0.23%)ofthedietbiomass.

[学科分类] 动物科学

[关键词] Diet