Infanticide in skimmers and terns: side effects of territorial attacks or inter-generational conflict?

Abstract. Chicks of colonial ground-nesting larids sometimes wander away from their home broods and are killed by neighbours, or occasionally adopted by foster parents. Hypotheses that explain infanticide in larids include selectively neutral infanticide during territory defence (selectively neutral territoriality) and prevention of misdirected parental care (inter-generational conflict). Some of the data from black skimmer, Rynchops niger, and common tern, Sterna hirundo, colonies are consistent with the inter-generational conflict hypothesis and inconsistent with the selectively neutral territoriality hypothesis.