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i Modeling of Populations and Metapopulations The Florida scrub -jay has been the subject of rigorous time -specific probability of persistence models (Fitzpatrick et at 1991; Woolfenden and Fitzpatrick 1991; f references in Breininger et at 1996b; Fitzpatrick et al. 1994a). These demographic models suggest that populations of at least 400 territories have a 99% probability of survival for 100 years and are referred to as "core" populations (Fitzpatrick et a/. 1994a). "Satellite" populations are composed of at least 100 breeding pairs of scrub -jays and have an 85 to 90% probability of survival for 100 years (Fitzpatrick et at. 1994a). A subpopulation with less than 10 breeding pairs has about a 50% probability of extinction within 100 years (Fitzpatrick et a/. 1991; Fitzpatrick et a/. 1994a; Stith et al. 1996). Florida scrub -jays generally disperse up to 2 miles with normal maximum dispersals ranging up to 5 miles in suitable habitat (Fitzpatrick et al. 1994x). Thus, breeding territories within 2 miles of one another are considered part of the same population or subpopulation (Stith et al. 1996; Fitzpatrick et al. 1994a). A metapopulation is comprised of a group of interbreeding subpopulations that are separated from one another by no more than 5 miles (Fitzpatrick et al. 1994a). Small subpopulations of jays are even less likely to go extinct if located within the normal 2 mile dispersal radius of neighboring scrub -jay subpopulations (Woolfenden and Fitzpatrick 1991; Fitzpatrick et al. 1994al. Population modeling suggests that a strong correlation exists between habitat quality and scrub -jay population extinction risk (Breininger et al. unpublished manuscript). Habitat models predict population declines of 25% every five years in large unburned tracts (Breininger et al. 1996b). Population modeling suggest that scrub -jay population increases after restoration to optimal habitat will be slow. These relationships suggest that scrub restoration activities should be prioritized in areas that have scrub -jays remaining or are proximal to scrub -jay subpopulations at risk (Breininger et aG unpublished Manuscript). This conclusion is based on slow population responses expected in unoccupied ,areas and the severe declines occurring in existing populations attributed to infrequent burning. Although local populations of scrub -jays have become extremely small in many ureas, probabilities of extirpation remain predominantly affected by habitat loss, habitat degradation through fire suppression, and stochastic influences on population dynamics (Woolfenden and Fitzpatrick 1984; Fitzpatrick et at. 1994a). In addition, the Florida scrub -jay has a sedentary social system that naturally creates small effective population sizes and increased levels of inbreeding (Woolfenden and Fitzpatrick 1984). Although rnatings between immediate family members are rare, matings between first -cousins, second -cousins, and other close relatives are quite common, even in large, contiguous populations (Woolfenden and Fitzpatrick 1978). For _ these reasons, the species exhibits reduced genetic variability compared to the western scrub -jay (Aphelocoma ca ilornicus) and other 22