Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection probability of breeding Florida Scrub-Jays (Aphelocoma coerulescens) and to estimate bird transition probabilities from one territory quality state to another. Our study sites were along central Florida's Atlantic coast and included two of the four largest metapopulations within the species range. We developed Markov models for habitat transitions and compared these to bird transition probabilities. Florida Scrub-Jay detection probabilities ranged from 0.88 in the tall territory state to 0.99 in the optimal state; detection probabilities were intermediate in the short state. Transition probabilities were similar for birds and habitat in grid cells mapped independently of birds. Thus, bird transitions resulted primarily from habitat transitions between states over time and not from bird movement. Survival ranged from 0.71 in the short state to 0.82 in the optimal state, with tall states being intermediate. We conclude that average Florida Scrub-Jay survival will remain at levels that lead to continued population declines because most current habitat quality is only marginally suitable across most of the species range. Improvements in habitat are likely to be slow and difficult because tall states are resistant to change and the optimal state represents an intermediate transitional stage. The multistate modeling approach to quantifying survival and habitat transition probabilities is useful for quantifying habitat transition probabilities and comparing them to bird transition probabilities to test for habitat selection in dynamic environments.

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Breininger eta [. landscape Patterns of Scrub Jay Populations 1443 ltdad. Las dreas con parches menores de 1 hectdrea de bosques abtertos de roble fueron usualmente poblaclones sumtdero. Los bosques abiertos de robles fueron parches menos inflamables en los paisajes sujetos a fuegos frecuentes. Las fuentes de poblacl6n vartaron temporal y espaclalmente debtdo a los fuegos y a la l)otenclaltdad de los sttlos para mantener chaparrales de enclnos (suelos). E1 andltsts de los patrones y la dindmica del paisaje indic6 que el mapeo del hdbttat debe inclutr no s6lo los parches del hdbttat real 6ptimo stno tambtdn los patsajes asoclados con los bosques abtertos de robles. Las influenclas de los patrones del patsaje sobre el uso del hdbitat, el dxtto reproducttvo, la sobre y el tamaflo del territorio puede ser cuantiflcado a dtferentes escalas comenzando con los atrlbutos asoclados con el hdbitat de los parches, los sttlos de nidiflcacl6n y los terrttorios. Sin embargo, existen errores potenclales de mapeo cuando se utiltzan hdbitats para cuanttflcar el areas de las fuentes y sumidero y otoros atributos poblaclonales stmtlares que son tmportantes para la persistencla de las espectes.

The concept of source and sinks can guide conservation, but empirical studies are needed to demonstrate that this concept applies to the real world. We investigated whether the source–sink concept could help to clarify the influence of habitat potential (scrub ridge characteristics), population density, and fires (shrub heights) on Florida Scrub‐Jay (Aphelocoma coerulescens) demography and dispersal. We mapped territories and measured survival, recruitment, emigration, immigration, and shrub heights annually for 12 years. We classified territories as oak if they overlapped well‐drained ridges, oak–palmetto if they overlapped poorly drained ridges >0.4 ha, and palmetto–oak if they only overlapped poorly drained ridges <0.4 ha. Territory size differed little among these categories but was negatively correlated with the annual number of breeding pairs, which ranged from 12 to 27. Scrub ridge characteristics influenced the locations of sinks and potential sources, whereas population density and fires caused temporal variation in demographic success. Oak territories were usually sources because they were net exporters of individuals and because recruitment exceeded mortality. Oak–palmetto territories sometimes functioned as sources but were often pseudo‐sinks because density dependence caused mortality to exceed recruitment. Palmetto–oak territories were true sinks because they were net importers of individuals and mortality exceeded recruitment regardless of population density. All scrub was short (<1.2 m) or medium height (1.2–1.7 m), but the spatial arrangement of these height classes changed regularly because fires occurred every 2–7 years. We observed a quadratic relationship between demographic success and the area of medium‐height scrub within territories. Territories that had 0.9–1.2 ha of medium‐height scrub had the highest demographic success. Applying source–sink concepts at the territory scale was useful to quantify habitat variation at a spatial scale relevant to population processes, reserve design, and habitat management. Our approach can be applied by using territory maps or geographic information systems to partition heterogeneous landscapes into territories and then by classifying territories into potential sources and sinks using scrub ridge characteristics and shrub heights.

The combined effects of habitat quality, breeder experience and sociobiology on population demography are poorly understood. Natural fire regimes, which influence habitat quality and sociobiology, have been replaced by controlled fire management in most ecosystems. Managing fire mosaics (vegetation at different ages since fire) can be important to sustain species in fire-maintained habitats, but requirements are usually poorly defined. Source-sink theory provides a foundation to quantify such habitat heterogeneity, but source-sink applications are largely focused on modeling. We quantified how habitat quality, breeder experience and non-breeding adult helpers affected Florida scrub-jay (Aphelocoma coerulescens) recruitment to describe source-sink heterogeneity within local populations. We used 22 years of census data of uniquely marked Florida scrub-jays to measure recruitment at 36 sites and combined that data with habitat-specific survival to characterize habitat-specific demography. To define habitat quality at the territory scale, we used static habitat features (soils, scrub oak cover) and dynamic habitat states (shrub heights and open sandy patches) that resulted from fire mosaics. Habitat quality most affected recruitment followed by the presence of helpers; fire mosaics, described by habitat states, determined whether territories functioned as strong sources, weak sources or sinks. Subdividing landscapes into habitat states allowed quantification of the fire mosaic at the territory scale and population scale, as the proportions of habitat states can predict local population growth rates. Our approach provides an example of how characterizing habitat quality at the territory scale, relative to source-sink categories, can explain habitat heterogeneity within local populations and inform fire management. bs_bs_banner Animal Conservation. Print