Postfledging parental effort in barn swallows: evidence for a trade-off in the allocation of time between broods

In altricial birds, parental care after fledging should be terminated as soon as the benefits from deserting the young outweigh those from continuing parental care. In seasonal environments, multiple breeders may trade off fitness benefits of the time invested in the care of fledglings of one brood against the benefits of an advanced start of the subsequent clutch. Using radiotelemetry of 494 fledglings in 114 families (of 88 pairs) of the...