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scrub, with much higher renesting attempts (3 to 4) and double brooding (20%) than in native habitats (Fitzpatrick et at. 1994a; Toland unpubl. data). The loss of native scrub plants and introduction of ornamental vegetation alters the predominant shrub species in disturbed sites, causingmore variation in scrub -jay nest sites than in natural habitats. In intensively developed suburbia, scrub -jays often nest higher than in native scrub and almost exclusively in non-native shrubs and trees (Fitzpatrick et al. 1994a). In large, natural habitats, Florida scrub -jays generally retain their territories and attract new replacement mates following the death of their spouse (Woolfenden and Fitzpatrick 1984; Breininger et at 1996b). In fragmented populations, females frequently disperse, often for long distances, after the death of a mate until they find an available male in another habitat patch (Breininger 1999). Conversely, Breininger (1999) found that dispersals by males within fragmented residential landscapes are limited to nearby clusters where they become nonbreeders until a breeding vacancy becomes available in the cluster of their residence. Breininger (1999) found that males represent the limiting sex in a cluster even when the total population had fewer females. Thaxton and Hingtgen (1996) reported that scrub -jays usually moved from small suburban scrub fragments into larger tracts of scrub and not from large tracts into smaller fragments. Once extinction occurred within the suburban scrub fragment the potential for recolonization of the abandoned habitat fragment by scrub -jays from larger tracts is low (Breininger 1999). Dispersals by either sex may be limited across fragmented residential landscapes if extinction :occurs in intervening fragments, as dispersing scrub -jays may be influenced by the presence of other scrub -jays and not just the availability of scrub habitat (Stith at al. 1996). The value of maintaining scrub -jays in suburban habitat fragments is that they may be an important source, although temporary, of individuals to colonize unoccupied, potential scrub -jay habitat areas following restoration to suitable habitat conditions (Breininger 1999). These above findings have several conservation management implications: 1.) where possible, scrub -jay reserves should be close together (within 1 ± mile 11.6 km)) to accommodate the low dispersal tendencies of reales (Breininger 1999); 21 scrub habitat patches within tile suburban residential rnatrix must bo managed for �., optimal scrub -jay habitat conditions to maximize demographic success within the patch (Fitzpatrick et at 1994a; Breininger 1999), and 3.) Scrub fragments should be maintained no more than 2.6 miles (4.2 krn) to facilitates the dispersal of fernales across the suburban landscape (Breininger 1999). The contribution of scrub -jay clusters residing in suburban/urban fragments to the long teen population size of their associated metapopulation is expected to be minimal because Of the poor demographic success exhibited by these fragmented clusters (Broininger 1999). 21