Increased lifetime reproductive success for Siberian jay (Perisoreus infaustus) males with delayed dispersal

In a crowded environment the natal territory could serve as a haven for you ng and inexperienced offspring until a breeding vacancy emerges. Delayed di spersal and association with kin could then offer adaptive benefits through an individual fitness gain. Here we report that delayed dispersal is assoc iated with a higher lifetime individual fitness in Siberian jay (Perisoreus infaustus) males. Sons bred more successfully and had more reproductive ev ents in life when they delayed dispersal. The higher lifetime reproductive success when sons disperse later in life is sufficient to promote postponem ent of natal dispersal, suggesting that dispersal is delay-ed due to ecolog ical constraints on access to high-quality habitats. We argue that the main tenance of this variation in the timing of dispersal and reproductive succe ss can be reconciled with non-genetic mechanisms driving dispersal. Social dominance within broods reflecting environmental conditions during growth i s such a mechanism.