Nepotistic vigilance behavior in Siberian jay parents

Many Siberian jay offspring (up to 50%) postpone independence and stay with their parents for up to 3 years. Parents offer such nondispersers a benefit in that they increase their vigilance while feeding together with retained offspring. In contrast, parents reduce their vigilance while in company of nonrelated flock members according to the many eyes principle. The preferential treatment offered by the parents provides an incentive for offspring to forego dispersal. Given evidence for mortality via surprise attacks by predators (goshawks), such nepotistic vigilance by parents could have a bearing on offspring survival and thereby promote delayed dispersal.