BUG-EGGS? ENABLE PARENTAL SAMPLING AND CHARACTERIZATION OF THE GENETIC MATING SYSTEM OF CATTLE EGRETS

ELAINE DANTAS DE SOUZA; MIÑO, CAROLINA ISABEL; CORTIÇO CORRÊA RODRIGUES, VERA LÚCIA; VALDES, TALITA ALVARENGA; EMMANUEL MORALEZ-SILVA; SÍLVIA NASSIF DEL LAMA

Puerto Iguazu

Congreso; I Ornithological Congress of the Americas; 2017

Association of Field Ornithologists-Aves Argentinas-Sociedade Brasileira de Ornitologia

Breeding in dense colonies during a limited time-period, characteristics of manywaterbirds ? herons, egrets and spoonbills ? may have promoted the evolution of nonmonogamous reproductive tactics. Yet, to date, only a handful of studies haveinvestigated the genetic mating systems of waterbirds, mostly because the difficulty ofsampling elusive candidate parents has hindered the application of conventional DNAbased parentage tests. Here, we characterize the genetic mating system of CattleEgrets Bubulcus ibis breeding in a natural colony located on trees. Using, for the firsttime, the Neotropical bug Panstrongylus megistus contained in fake fiber-glass eggs, wecollected blood from incubating males and females in 31 nests. We drew blood from thenestlings (n = 89) at those nests, and genotyped all samples at 14 microsatellites. In linewith previous behavioral observations, we found evidence supporting a nonmonogamous genetic mating system in Cattle Egrets. The parentage allocation methodinferred extra-pair paternity (EPP) in 62% of nests and conspecific brood parasitism(CBP) in 64% of nests, while the kinship classification of nestlings in broods disregardingparental information inferred EPP in 50% and CBP in 43% of nests. These results indicatethat inferences about the genetic mating system made in the absence of parentalinformation could underestimate the ?true? rates of alternative reproductive tacticsoccurring in nature. We expand knowledge on the genetic mating system of colonialwaterbirds, highlight the importance of including parental samples in these analyses,and contribute new information to guide management strategies of the highly invasiveCattle Egret.