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• E l- Long-term studies at Kennedy Space Center (KSC), located on Merritt Island, Brevard County, Florida, found that scrub -jays occupy a broad range of habitat conditions, including areas that are marginal for them (Schmalzer et al. 1994). However, r demographic success studies at KSC suggest that mortality exceeds reproductive success in areas on KSC that do not exhibit optirnal scrub Jay habitat conditions. as described by Woolfenden and Fitzpatrick (1984), Fitzpatrick et al. (1991), and Breininger 1992 (Schmalzer et aL 1994). The open canopy and low shrub community structure of optimal scrub -jay habitat landscapes enhance habitat defendability as it provides the perched scrub -jay with a full view of its territory and an unobstructed flight path for the rapid defense of territorial boundaries (Woolfenden and Fitzpatrick 1984). The low, open vegetative community structure of preferred scrub jay habitat also allows for effective surveillance of both aerial and ground predators (Woolfenden and Fitzpatrick 1984). Predation, particularly by hawks, is the primary cause of Florida scrub -jay mortality (Woolfenden and Fitzpatrick 1984). Florida scrub -jays residing in large landscapes surrounded by other scrub -jay families are safer from predation than isolated families living in fragmented edge habitats due to the early warning system that is provided by the contiguous families (Breininger et al. 1996b). Maintenance of an open habitat landscape structure also enhances population persistence as it provides an opportunity for nonbreeders to detect vacancies in their surroundings and disperse into these areas with reduced chance of predation from woodland hawks (Breininger et al. 1996a). The effectiveness of the scrub -jays' important territorial defense and predator surveillance behavior is significantly reduced in tall, disturbed scrub and wooded matrix habitats (Fitzpatrick et aL 1991; Breininger et al. 1991, 1995, 1996b). The increased presence of avian competitors within tall, overgrown or wooded habitats and the reduction in the visual range of the sentinel, which exposes the scrub -jay group to surprise attacks by aerial predators, such as hawks, are factors which reduce habitat quality (Breininger et al. 1991, 1995). Adult mortality is high and reproductive success is low for scrub -jay groups residing within tall, disturbed habitat types (Woolfenden and Fitzpatrick 1984; Fitzpatrick et aL 1991; Schmalzer et al. 1994). Fragmentation of native habitats and replacement with urban habitats increases the densities and hunting efficacy of nest predators such as fish crows (Corvus ossitragus), raccoons (Procyon lotor), and house cats (Felis catus) that are much less common in optimal xeric oak scrub habitat (Breininger 1999). Fragmented and urbanized landscapes also increase the numbr:rs of potential competitors like the blue jay (Cyanocitta cristata) (Fitzpatrick et aL 1991; Breininger 1999). The intervening landscape matrix affects scrub -jay dispersal behavior (Fitzpatrick et al. 1994a). Protected scrub habitats most effectively sustain scrub -jay