Adoption of unrelated young by Greater Rheas

Abstract

Abstract.--The benefits, if any, of the adoptive behavior of male Greater Rheas (Rhea americana) towards unrelated young while leading their offspring are not known. Therefore, we quantified adoption by Rheas in an agricultural area of Rio Grande do Sul, Brazil, in order to quantify the potential benefits and the recipientso f theseb enefitsA. dult malesf requently adopted (23%), were more vigilanta nd protectivet han non-adoptersa, nd ended up leading larger groups of young than non-adopting males. The adopted chicks were usually not more than 1-wk old and survived in greater proportion than the adopter's own offspring.