Abundance, Nest Sites, and Nesting Success of Steller's Jays Along a Gradient of Urbanization in Western Washington

We studied abundance, nest site characteristics, and nest success of Steller's jays (Cyanocitta stelleri) in western Washington from 1996 to 2002. This common but relatively understudied species is a nest predator that may limit the reproductive success of other species. Jays were more abundant at sites on the Olympic Peninsula than at sites in the Seattle area. On the Olympic Peninsula, jays were more abundant in fragmented than contiguous forest stands. In the Seattle area, jays were detected at exurban, suburban, and urban sites, but their abundance was marginally higher at suburban sites. Jay nests in the exurban and wildland forests of the Olympic Peninsula were frequently successful, but those in suburban Seattle rarely were, possibly because of lower nest predator populations and reduced human disturbance on the Olympic Peninsula. Nest site characteristics were similar in all study areas. Thus, while Steller's jays may be visible members of avian communities near human settlements and recreation areas, we hypothesize that this habitat is of lower quality than fragmented forest away from humans. Because jays concentrate their activities, including nesting, along edges and are most abundant in suburban and fragmented forest areas, other birds nesting along edges in these areas may be at increased risk of nest predation.