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Spatiotemporal responses of bats to fire are not well understood. Fire can indirectly influence bat activity through changes to understory vegetation, insect prey availability, and roost tree abundance. High-flying bats may be less influenced by fire-induced changes to the understory because they forage above the forest canopy. Fire-dependent forests are prevalent across the range of the endemic Florida bonneted bat (Eumops floridanus), a large, high-flying, and critically endangered species, yet effects of fire management on this species are completely unknown. To investigate short-term responses of these bats to fire, we conducted pre-post-treatment-control experiments in 4 prescribed burns during 2 seasons (dry, wet). For 12 nights preburn and 24 nights post-burn, we surveyed bat activity acoustically at 3 sites within each burn (treatment) and 3 adjacent sites (control). Using mixed-effects models to test the effect of treatment on bat activity, we found that bat activity significantly increased post-burn in treatment sites relative to control sites, with more pronounced effects during dry season burns. We also detected significantly more feeding buzzes (foraging activity) in treatment sites than control sites, and a negative trend over time in the burn effect size post-burn. We suggest that bats are attracted to increased availability of insect prey immediately following burns, particularly during the dry season when prey may be limited. Our results suggest that burns have short-term positive effects on Florida bonneted bats and that restoring fire to fire-dependent forests may improve foraging habitat for this species. [ABSTRACT FROM AUTHOR]

We conducted the most intensive estimate of the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) metapopulation to date using pellet surveys and capture-recapture methodology. We livetrapped 83 rabbits, evaluated 5 closed population models, and selected the model that best represented the data. We considered the variation in behavioral response model the best model and correlated (r2 = 0.913) its patch population estimates to patch pellet densities. From the prediction equation, we generated a range-wide metapopulation estimate of 317 rabbits, a western clade population of 257 rabbits, an eastern clade population of 25 rabbits, and translocated marsh rabbit populations of 35 and zero on Little Pine and Water keys, respectively. A subset of patches whose marsh rabbit subpopulations were last estimated in 1993 exhibited a 46% decline in abundance over 15 yr. Due to the low estimate of the eastern clade population, special effort should be initiated to avoid loss of genetic diversity. The prediction equation suffers from limited data at high pellet densities, patches with ≥5 pellets/m2. Future studies should investigate if the slope of the regression is indeed near 1 by sampling patches across the range of pellet densities, especially those with ≥ pellets/m2. The equation provides managers a quick, efficient, and noninvasive method to estimate marsh rabbit abundance from pellet counts but the confidence of predicted rabbit densities from high pellet density patches is low. [ABSTRACT FROM AUTHOR]

The endangered Florida Key deer (Odocoileus virginianus clavium) is endemic to the Lower Florida Keys. In recent years, habitat fragmentation and restricted dispersal have resulted in small, isolated herds on some islands. Recovery biologists proposed translocations to increase the island herds that had declined or remained low; however, efficacy of Key deer translocations had yet to be evaluated. Our objective was to evaluate survival, ranges, reproduction, and dispersal of translocated deer. During 2003-2005, we translocated 39 adult or yearling deer to Sugarloaf (approx. 19 km from trap site; 10 M, 14 F) and Cudjoe (approx. 15 km from trap site; 6 M, 9 F) keys. We kept deer in large, high-fenced holding pens (Sugarloaf = 7.7 ha, Cudjoe = 10.7 ha) on the destination islands for 3-6 months (i.e., soft release). We observed low mortality (n=6 mortalities) of translocated deer with average annual survival (S) of 0.796 for both sexes. We found translocated deer had larger seasonal ranges than did resident deer (i.e., those located on Big Pine and No Name keys). In evaluating effects of acclimation period on ranges and dispersal, we found no difference in 95% ranges or 50% core areas ≤4 month postrelease versus 4-8 months postrelease. We found, however, postrelease dispersal distances were dependent on time kept in pen. Only 2 of 39 (5%) translocated deer left the destination islands by the end of the study. With high survival and low dispersal indicating success, we credit soft release translocation in establishing deer herds on Sugarloaf and Cudjoe keys. Our data support translocations as an effective strategy for creating sustainable outer-island Key deer herds. [ABSTRACT FROM AUTHOR]