The critically endangered Florida grasshopper sparrow (Ammodramus savannarum floridanus) is dependent on dry prairies managed with prescribed fires that are applied every 1–3 years. Timing of prescribed fires shifted from predominantly the dormant season (Jan–Mar) to the transition (Apr–Jun) and growing (Jul–Aug) seasons starting in the early 2000s to better mimic natural fire regimes. Populations have continued to decline, however, and the presumption that natural fire regimes are beneficial to the small extant Florida grasshopper sparrow populations needs to be evaluated. We monitored 167 Florida grasshopper sparrow nests across 6 fire treatments at Three Lakes Wildlife Management Area, Osceola County, Florida, USA, 2013–2016, and investigated the role of fire season and interval on clutch initiation date, nest site selection, nest survival, productivity, and nestling mass. Clutch initiation was delayed by ≥33 days in prairies burned during the current transition season and we found no nests in prairies burned during the current growing season. Transition season burns also overlapped with the early breeding season, which could result in the destruction of nests. Clutches were larger at the beginning of the breeding season and nestling mass was highest in the middle of the breeding season, indicating that early and mid‐season nests may be more valuable to annual fecundity than late‐season nests. Florida grasshopper sparrows nested in prairies burned in the current dormant season or previous growing season more than expected based on their availability and as expected or less than expected in prairies burned in the current transition season, previous transition season, previous dormant season, or >2 years ago. However, we found no effect of fire treatment on daily nest survival, clutch size, number of fledglings per successful nest, or nestling mass. We recommend dormant season burning in prairies occupied by Florida grasshopper sparrows to increase reproductive potential given the subspecies’ small population and the importance of each nest attempt to population growth. We recommend transition or growing season burns in unoccupied adjacent prairies to maintain high‐quality dry prairie for nesting in future years. Prescribed fire management goals for Florida grasshopper sparrow populations should be guided by demographic responses rather than natural fire regimes. © 2019 The Wildlife Society.

The eastern spotted skunk (Spilogale putorius) is a species of conservation concern in much of its range and has experienced a decline since the early to mid‐1990s. But the subspecies that inhabits peninsular Florida, the Florida spotted skunk (S. p. ambarvalis), might still be abundant and is an important nest predator of the endangered Florida grasshopper sparrow (Ammodramus savannarum floridanus). To gain insight on this little‐studied subspecies and inform potential management strategies, we conducted a resource selection study on the Florida spotted skunk. We examined 5 hypotheses for den site selection related to den type, vegetation, and landscape characteristics in a dry prairie ecosystem in central Florida. We tracked 36 individual skunks to 757 den sites. Using discrete choice analysis, we found that male and nonbreeding female skunks at our study site were 5 times more likely to select a mammal burrow over a gopher tortoise (Gopherus polyphemus) burrow, that selection of a den site increased 34% for each 1‐burrow increase in the number of nearby burrows, and that selection of a den site increased 3% for every 10‐cm increase in a visual obstruction index. Similarly, breeding female skunks were more likely to select mammal burrows and shallow depressions over gopher tortoise burrows by 16‐fold and 13‐fold, respectively, and selection of a den site increased by 75% for every 1‐burrow increase in the number of nearby burrows. In contrast to previous studies that occurred in forested, mountainous environments elsewhere in the species' range, our findings suggest that den characteristics might be more important than landscape or vegetation characteristics to Florida spotted skunk den site selection in dry prairie. Additionally, the frequency of prescribed fires on the landscape did not appear to affect Florida spotted skunk den site selection. Thus, Florida spotted skunks in this ecosystem might be landscape generalists, thereby potentially limiting the ability of managers to control nest predation by this subspecies through habitat management. © 2019 The Wildlife Society.

Increasing nest survival by excluding predators is a goal of many bird conservation programs. However, new exclosure projects should be carefully evaluated to assess the potential risks of disturbance. We tested the effectiveness of predator exclosure fences (hereafter, fences) for nests of critically endangered Florida Grasshopper Sparrows (Ammodramus savannarum floridanus) at a dry prairie site (Three Lakes; 2015-2018) and a pasture site (the Ranch;-2016 in Osceola County, Florida, USA. We installed fences at nests an average of 8 days after the start of incubation, and nest abandonment after fence installation was rare (2 of 149 installations). Predation was the leading cause of failure for unfenced nests at both sites (48-73%). At Three Lakes, nest cameras revealed that mammals and snakes were responsible for 61.5% and 38.5% of predation events, respectively, at unfenced nests. Fences reduced the daily probability of predation (0.016 for fenced nests vs. 0.074 for unfenced nests). The probability that a fenced nest would survive from discovery to fledging was more than double that of unfenced nests (60.4% vs. 27.7%). However, we found no difference in daily nest survival at the Ranch between the year before nests were fenced (2015; 0.874) and the year when all but one nest were fenced (2016; 0.867) because red imported fire ants (Solenopsis invicta) were responsible for 86% of predation events at fenced nests at the Ranch. The use of cameras at fenced nests revealed that site-specific differences in nest predators explained variation in fence efficiency between sites. Our fence design may be useful for other species of grassland birds, but site-specific predator communities and species-specific response of target bird species to fences should be assessed before installing fences at other sites. RESUMEN.Cercas de exclusi on alrededor de nidos de Ammodramus savannarum floridianus en riesgo disminuyen las tasas de depredaci on por mam ıferos Incrementar la supervivencia de los nidos mediante la exclusi on de depredadores es uno de los objetivos de muchos programas de conservaci on de aves. Sin embargo, nuevos proyectos de exclusi on deben ser evaluados cuidadosamente para determinar el riesgo potencial del disturbio. Evaluamos la efectividad de cercas excluyentes de depredadores (cercas de aqu ı en adelante) para nidos del cr ıticamente amenazado Ammodramus savannarum floridianus en un sitio de pradera seca (Three Lakes; 2019-2018) y un sitio de potrero (the Ranch; 2015-2016) en el condado de Osceola, Florida, USA. Instalamos cercas en los nidos en promedio ocho d ıas despu es del inicio de la incubaci on y el abandono del nido despu es de la instalaci on del acerca fue raro (2 de 149 instalaciones). Depredaci on fue la causa principal de fracaso de los nidos sin cercas en los dos sitios (60.4% vs. 27.7%). Sin embargo, no encontramos diferencias en la supervivencia diaria de los nidos en "the Ranch" entre los años anteriores a la instalaci on de las cercas (2016; 0.874) y el año en el que todos los nidos excepto...

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Recovery of listed species requires that land managers and research biologists work together to address the factors affecting population stability and growth. In Florida, an essential factor affecting rare species habitat quality and restoration is fire management. Fire plays an essential role in restoring and maintaining almost every upland ecosystem in Florida, but fires also have negative effects (e.g., mortality and displacement) that play out today within an altered landscape where rare species are often limited to small, fragmented areas and negative effects may be accentuated. Fire effects also are complex, not well studied experimentally, and likely to change as urbanization and global temperatures increase over coming decades. These conditions can create missteps in both fire research and fire management without regular communication between scientists and practitioners. We assessed the fire-related research associated with four federally listed birds in Florida: Cape Sable seaside sparrow (Ammodramus maritimus mirabilis), Florida grasshopper sparrow (Ammodramus savannarum floridanus), Florida scrub-jay (Aphelocoma coerulescens), and red-cockaded woodpecker (Dryobates borealis). Fire research has not addressed the needs of some of these species for starkly different reasons. Land managers, in turn, have not successfully applied the recommendations of fire research in other instances. Our results point to fire frequency as an important focus for practitioners managing habitat for rare species in Florida. Our review also suggests that successful integration of research and management will be best served when (1) ecological burning practices are used, (2) local fire management goals are prioritized annually, (3) instructional products are developed for managers, (4) land manager tenure is promoted, (5) stakeholders meet regularly, and (6) creative solutions are devised to overcome staff and equipment shortages.