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Pocket gophers provide vital ecosystem services; however, species like the southeastern pocket gopher (Geomys pinetis), endemic to the southeastern United States, are declining. Long-term conservation of this species requires greater understanding of its habitat characteristics. Our objective here was to determine habitat features associated with southeastern pocket gopher occurrence at the local (100 ha) and home-range (0.09 ha) scales. We assessed occurrence and carried out vegetation surveys at 177 sites across the species’ range during the growing season (March–September) 2016–2017. At the local scale, we found a negative relationship between occurrence and groundcover height and a quadratic relationship with canopy closure. At the home-range scale, occurrence was positively related to grass groundcover and had a quadratic relationship with canopy closure. Restoration of southeastern pocket gopher habitat should focus on creating or maintaining areas with intermediate canopy (~45–55%) and an understory dominated by grasses and forbs.

Total mercury (THg) concentrations were measured in wild alligators inhabiting a coastal marsh in southern Louisiana, to determine the tissue distribution of THg among various body organs and tissue compartments. Concentrations of THg in claws and dermal tail scutes were compared to those in blood, brain, gonad, heart, kidney, liver, and skeletal muscle to determine if the former tissues, commonly available by non-lethal sampling, could be used as measures of body burdens in various internal organs. Mercury was found in all body organs and tissue compartments. However, overall, THg concentrations measured in alligators were below the FDA action level for fish consumption and were comparable to previous data reported from southwestern Louisiana. Our results suggest consumption of meat from alligators found in this region may be of little public health concern. However, the extended period of time between sampling (in this study) and the present-day highlight the need for continuous, additional, and more recent sampling to ensure consumer safety. Total mercury concentrations were highest in the kidney (3.18 ± 0.69 mg/kg dw) and liver (3.12 ± 0.76 mg/kg dw). THg levels in non-lethal samples (blood, claws, and dermal tail scutes) were positively correlated with all tissue THg concentrations (blood: R

Biofluorescence in mammal pelage is considered rare, but has been documented in multiple taxa in recent years. Herein, we provide the first observations of biofluorescence in fossorial mammals. We documented biofluorescence in live Geomys pinetis (southeastern pocket gopher) and in museum specimens of four additional geomyid species. Although unknown, the adaptive significance of biofluorescence in pocket gophers is likely similar to that documented in terrestrial and arboreal species previously, including communication or predator evasion.

Animals living underground deal with multiple physiological challenges, such as hypoxia and hypercarbia, but may have reduced thermoregulation demands because of the more stable underground microclimate. Southeastern pocket gophers (Geomys pinetis Rafinesque) occur in the fire-adapted, open-pine forests of the southeastern Atlantic Coastal Plain where prescribed fire is commonly used to manage understory vegetation. They are almost exclusively fossorial, and their tunnels provide ecological services, including shelter, for a suite of commensal vertebrates and invertebrates. To quantify potential thermoregulation benefits of southeastern pocket gopher tunnels, we compared temperatures in active tunnels (n = 31) to aboveground temperatures during winter (December 2018–February 2019), and to aboveground temperatures during prescribed fire events (n = 16) occurring in spring (March–May 2019). During winter, tunnels provided a more stable thermal environment (average range = 6.5 ± 0.8 C; mean ± se) relative to aboveground (average range = 24.8 ± 1.8 C) temperatures. Similarly, mean tunnel temperature range (2.05 ± 0.5 C) was significantly narrower than aboveground temperature range associated with fire events (497.0 ± 101.4 C). Clearly, tunnels provide a stable thermal environment for pocket gophers and commensals that use their tunnel systems.

Mortality from white-nose syndrome has made management and recovery of the northern long-eared bat (Myotis septentrionalis) a priority. Ensuring availability of diurnal summer roosts, where gestation and rearing of young occurs, is a critical component of successful recovery. However, observed variation in roost selection across the species’ range makes extrapolating data across physiographic regions and habitat types difficult, and limited information exists on roost selection at the southern range extent of the species. Therefore, we examined M. septentrionalis diurnal roost selection toward the southern range extent in northern Georgia, USA. We identified characteristics of desirable roosts for all individuals and for reproductive females by comparing roosts to surrounding vegetation and topographic characteristics at the plot, home range (67 ha), and landscape (17.2 km2) scales. From May to July 2014–2017, we radio tagged 12 female and 4 male M. septentrionalis and located 37 roosts. Bats roosted in cavities, loose bark, and hollow boles of 16 tree species. Over half of roosts (53%) were located below the canopy and in trees with larger diameters than surrounding trees. Bats disproportionately roosted in snags, with relative probability of selecting a snag roost increasing with snag density at the plot scale. On low gradient slopes, roosts occurred more frequently on west-facing aspects but as slope increased bats showed no aspect preference. Results indicate individuals in our study area are indifferent to or actively avoid roosts with high solar exposure. Our results support previous research that management efforts should focus on creating and retaining snags across the landscape and highlight the need for management to consider regional variation in habitat use.

Increased market viability of harvest residues as forest bioenergy feedstock may escalate removal of coarse woody debris in managed forests. Meanwhile, many forest invertebrates use coarse woody debris for cover, food, and reproduction. Few studies have explicitly addressed effects of operational-scale woody biomass harvesting on invertebrates following clearcutting. Therefore, we measured invertebrate community response to large-scale harvest residue removal and micro-site manipulations of harvest residue availability in recently clearcut, intensively managed loblolly pine (Pinus taeda) forests in North Carolina (NC; n = 4) and Georgia (GA; n = 4), USA. We captured 39,794 surface-active invertebrates representing 171 taxonomic groups using pitfall traps situated among micro-site locations (i.e., purposefully retained piles of hardwood stems and piles of conifer stems and areas without coarse woody debris in NC; windrows and no windrows in GA). Micro-site locations were located within six, large-scale treatments (7.16-14.3 ha) in clearcuts. Large-scale treatments represented intensive harvest residue removal, 15% and 30% harvest residue retention, and no harvest residue removal. In NC, ground beetles (Coleoptera: Carabidae) and crickets (Orthoptera: Gryllidae) were three times more abundant in treatments with no harvest residue removal than those with the most intensive harvest residue removal and were reduced in treatments that retained 15% or 30% of harvest residues, although not significantly. Invertebrate taxa richness was greater at micro-site locations with retained hardwood and pine (Pinus spp.) harvest residues than those with minimal amounts of coarse woody debris. In both states, relative abundances of several invertebrate taxa, including cave crickets (Orthoptera: Rhaphidophoridae), fungus gnats (Diptera: Mycetophilidae and Sciaridae), millipedes (Diplopoda), and wood roaches (Blattodea: Ectobiidae), were greater at micro-site locations with retained harvest residues than those with minimal coarse woody debris. Intensified woody biomass harvesting without retention of ≥15% of harvest residue volume may reduce invertebrate taxa richness and abundances of some key invertebrate taxa in regenerating stands. Further, harvest residue management during and after woody biomass harvesting may be an important consideration for maintaining invertebrate diversity and conserving invertebrates that are influential in the maintenance of ecosystem function and integrity in young forests.

Montane rock outcrops are a sensitive habitat type throughout the Appalachian Mountains. These areas provide habitat for a variety of endemic or rare fauna and flora species assemblages. Our objective was to conduct a status survey of focal mammal species considered rare in the Appalachian region, including Allegheny woodrat (Neotoma magister), eastern spotted skunk (Spilogale putorius), least weasel (Mustela nivalis), long-tailed weasel (Mustela frenata), and fisher (Martes pennanti) at rock outcrops in Shenandoah National Park, Virginia. From 7 May to 27 September 2015, we conducted camera surveys at 48 rock outcrop sites in the Park. Over 1,985 trap nights (TN), we obtained 2,572 images and detected 16 mammalian species. We quantified capture success, related success to a set of predefined landscape variables and determined co-occurrence patterns of various species. Allegheny woodrats had the highest capture success (10.7%; 212/1,985 TN); however, black bears (Ursus americanus) and raccoons (...

Geomys pinetis (Southeastern pocket gopher) is a fossorial rodent historically associated with Pinus palustris (longleaf pine) communities. Conversion and fragmentation of longleaf pine communities have reduced quality and quantity of southeastern pocket gopher habitat. It is therefore important to determine characteristics of suitable habitat for future conservation efforts focusing on maintaining or restoring appropriate habitat conditions. We quantified understory vegetation structure (i.e., ground cover categories) and soil characteristics (i.e., soil texture, pH, nitrogen, and carbon at multiple depths) in areas with and without pocket gopher activity. We evaluated a suite of models to determine whether understory vegetation structure, soil characteristics, or a combination of vegetation and soil characteristics were better predictors of gopher presence. Soil characteristics predicted pocket gopher presence better than understory vegetation structure with the best overall model combining per...

The southeastern pocket gopher Geomys pinetis is absent from a large portion of its historical range. Translocation may represent a viable management technique to reestablish populations into suitable habitat. However, several aspects of the species' ecology are poorly understood, making development of an effective translocation approach challenging. Therefore, we used radiotelemetry to examine home range, survival, dispersal, and daily activity patterns of the southeastern pocket gopher in southwestern Georgia. We measured soil and vegetation characteristics within individual home ranges and examined relationships between home range size, habitat variables, and body mass. Mean home range size of 17 radio-tagged pocket gophers was 921.9 m2 (range = 43.4–2246.8 m2). Home range size was positively related to body mass, percent silt at a depth of 25 cm, and soil carbon content at 75 cm and was negatively related to percent sand at 25 cm, percent clay at 50 cm, and ground cover of grasses other than wiregrass Aristida beyrichiana. Survival rate was 0.78 (range = 0.50–1.00) over the 51-wk study, and we documented predation, likely by avian predators, on two individuals. Three individuals dispersed, with a maximum dispersal distance of 319.1 m (range = 143.2–319.1 m), the farthest known southeastern pocket gopher dispersal. Pocket gophers exhibited greater activity from 0000 to 0400 hours and from 1600 to 2000 hours, contrasting previous research that southeastern pocket gophers were equally active throughout the diel period. Our home range size estimates for southeastern pocket gophers are the first determined using radiotelemetry and are considerably smaller than previous estimates. Although we documented dispersal distances more than 300 m, the fragmented nature of current and restored habitats likely will prevent large-scale natural colonization. Our results provide information important for maximizing success in future southeastern pocket gopher translocation efforts.

Harvest of low value trees and logging residues for bioenergy reduces downed wood post-harvest with potential indirect negative effects on ground-dwelling wildlife such as rodents. We assessed the influence of woody biomass harvests on rodent abundances using an operational-scale, randomized complete block experimental design study in North Carolina (4 blocks) and Georgia, USA (4 blocks). Each block contained 6 treatments randomly applied to a clearcut harvest, that varied by volume of woody biomass retained, and that represented existing woody biomass harvest recommendations. We livetrapped rodents in 2011–2013, calculated the minimum number known alive for each captured species, and used the value as an index of abundance. We compared abundance of the 3 most commonly captured species (deer mice [Peromyscus spp.], house mouse [Mus musculus], and hispid cotton rat [Sigmodon hispidus]) among treatments with generalized linear mixed effects models. We assessed relationships among species’ abundance and measurements of downed woody debris and vegetation in each treatment unit using linear regression. Although abundance varied among treatments in some cases, we did not detect consistent relationships between woody biomass retention treatments and abundance. Volume of downed woody debris in the treatment unit negatively influenced house mice but had varying influences on deer mice across years. Downed woody debris groundcover negatively affected deer mice in North Carolina in 2012. Litter groundcover negatively influenced deer mice and hispid cotton rats, whereas grass groundcover positively influenced the hispid cotton rat. The lack of consistent relationships between rodent abundance and volume of retained woody debris suggests that the rodent species captured in this study were not affected by current efficiencies of operational woody biomass harvests in southeastern United States loblolly pine (Pinus taeda) plantations. However, focal species were habitat generalists and less common species may have greater sensitivity to biomass harvests. © 2017 The Wildlife Society.

Many sympatric species use Gopherus polyphemus (Gopher Tortoise) burrows as refugia from predators, extreme temperatures, and fire. As part of an ongoing project involving trail-camera monitoring at Gopher Tortoise burrows, we observed a Sciurus niger (Eastern Fox Squirrel) sheltering in an occupied burrow twice in a single day. Eastern Fox Squirrels primarily forage on the ground, and Gopher Tortoise burrows likely offer refuge from avian predators but could expose Eastern Fox Squirrels to increased predation risk from mammalian and reptilian predators. Alternatively, the squirrel may have been seeking refuge from higher-than-average temperatures. Our observation further demonstrates the importance of Gopher Tortoise burrows to vertebrate fauna in the southeastern United States.

Numerous vertebrate species including Pituophis spp. (pine snakes) and birds of prey have been shown to consume Geomys pinetis (Southeastern Pocket Gopher), but its full spectrum of predators remains undocumented. As a part of a larger project involving radiotracking Southeastern Pocket Gophers in southwestern Georgia, a female Pocket Gopher was consumed by a Crotalus horridus (Timber Rattlesnake) while making an aboveground movement. Timber Rattlesnakes are a previously undocumented predator for Southeastern Pocket Gophers. Our observation further demonstrates predation risks associated with aboveground movement.

Increased market viability of harvest residues gleaned for forest bioenergy feedstocks may intensify downed wood removal, particularly in intensively managed forests of the Southeast. Downed wood provides food and cover for many wildlife species, including birds, yet we are aware of no study that has examined winter bird response to experimentally manipulated, operational-scale woody biomass harvests. Further, little research has investigated avian use of downed wood following timber harvests. As such, our objectives were to: (1) evaluate effects of varying intensities of woody biomass harvest on the winter bird community and (2) document spatial associations between winter bird species and available habitat structure, including downed wood, in regenerating stands. In January and February of 2012–2014, we surveyed birds using a modified version of spot-mapping in six woody biomass removal treatments in North Carolina, USA (n = 4 regenerating stands). Treatments included clearcut harvest followed by: (1) traditional woody biomass harvest with no biomass harvesting guidelines; (2) 15% retention with harvest residues dispersed; (3) 15% retention with harvest residues clustered; (4) 30% retention with harvest residues dispersed; (5) 30% retention with harvest residues clustered; and (6) no woody biomass harvest (i.e., reference). We tested for treatment-level effects on avian relative abundance (overall and individual species), species diversity and richness, and counts of winter birds detected near (∼1 m from pile), in, or on branches of downed wood piles and calculated proportional avian habitat use of harvest residues and vegetation in regenerating stands. In 69 visits over three winters, we observed 3352 birds in treatments. In 2013, counts of birds detected in piles were greater in the no biomass harvest and 30% clustered treatments than the no biomass harvesting guidelines treatment. In 2012 and 2013 combined, mourning dove (Zenaida macroura) had greater relative abundance in the no biomass harvest treatment compared to the 15% dispersed treatment and was more often detected within 1 m of downed wood piles than in vegetation. We counted more winter birds in and near adjacent forest edge than in treatment interiors each year. Overall, we detected minimal treatment effects on winter bird relative abundance and no effects on species diversity and richness. Relative abundance of winter birds increased over time as vegetative cover established in regenerating stands. Our results suggest woody biomass harvests in intensively managed pine forests had no effect on the winter bird community, but winter birds used harvest residues. Further, vegetation structure and composition, rather than availability of harvest residues, primarily influenced winter bird use of regenerating stands.

Perceptual-biases are important for understanding an animal's natural history, identifying potential ecological traps, and for developing effective means to monitor individuals and populations. Despite research demonstrating anurans having a positive phototactic response towards blue colors, we do not yet understand if color cues are used functionally beyond sexual selection. The aim of our study was to determine if color cues are used in selecting microhabitat, and if anuran's blue-positive phototactic response could increase selection of artificial PVC refugia used to monitor cryptic camouflaging anuran species. We captured 32 Cope's Gray Treefrogs and placed them in mesh enclosures with three PVC tubes painted blue, brown, and white. Concurrently, we placed blue, brown, or unpainted white PVC tubes in stratified arrays around a treefrog breeding pond, and counted the number of occasions treefrogs occupied different colored PVC tubes. In the confined choice experiment, treefrogs selected blue tubes (48.3%) significantly more often than brown (28.5%) or white (23.2%) tubes. Our field experiment mirrored these findings (52.0% of capture events in blue, 29.0% in brown, and 19.0% in unpainted white tubes). Our results suggest color influences Cope's Gray Treefrog microhabitat selection, and they utilize color vision when choosing refugia. We demonstrate simple, small changes based on perceptual-biases can induce behaviors that may in turn have large impacts on sampling techniques used in monitoring and inventorying. Incorporating non-traditional physiological measures into animal inventorying and monitoring programs can be used in the future to improve conservation efforts.

Little is known about common bottlenose dolphin (Tursiops truncatus) seasonal migration along the United States southeastern Atlantic coast, or what factors influence migratory patterns. Therefore, our objectives were to: 1) document evidence for seasonal movement of dolphins in this region (that would indicate migratory behavior) and 2) determine if seasonal changes in abundance and temporary emigration (i.e., migration indicators) for dolphins along South Carolina and Georgia coasts are related to changes in water quality variables. Previously collected capturerecapture data (from visual sightings of individual dolphins) and water quality data from Charleston, South Carolina and St. Catherine’s Island, Georgia were used to achieve our objective. Robust design models were used to estimate seasonal abundance and temporary emigration for the Charleston population, whereas closed population capture-recapture models were used to estimate seasonal abundances for the St. Catherine’s Island population. The Charleston population showed seasonal abundance and temporary emigration patterns with low estimates in winter, which increased in spring, peaked in summer, and decreased in fall. Seasonal temporary emigration was best explained by water temperature, which followed the same general pattern. Seasonal abundance in the St. Catherine’s population was best explained by salinity, but no consistent pattern in abundance was observed. Our results not only provide the first evidence of a clear seasonal migration of dolphins in this region, but can aid in conservation and management efforts by increasing accuracy of abundance estimates.

Site-occupancy of bats in forested landscapes has been linked to vegetation clutter, but clutter alone may not sufficiently explain observed site-occupancy. Abundance of prey likely has a strong influence on habitat use in forest landscapes as well. Therefore, we simultaneously examined influence of insect abundance and vegetation characteristics on bat site-occupancy across 3 pine (Pinus spp.)-dominated landscapes within the southeastern U.S. Coastal Plain. We conducted acoustic surveys and used Akaike’s Information Criterion to evaluate plausibility of occupancy and detection models that incorporated vegetation- and insect-related factors. Results indicate that bat site-occupancy was better explained by a combination of vegetation characteristics and insect abundance than either separately, and vegetation structure has a stronger influence than prey abundance. Additionally, our data generally suggest insect taxon is more influential in predicting occupancy than insect size. Management activities on pine-dominated landscapes that simultaneously reduce vegetation clutter and increase insect abundance are likely to benefit resident bat species.

In the fire maintained longleaf pine (Pinus palustris) ecosystem, underground refugia such as gopher tortoise (Gopherus polyphemus) burrows and stump holes may be important for animals to escape fire and extreme temperatures. Despite being documented as refugia for several species of concern including the black pine snake (Pituophis melanoleucus lodingi) and eastern diamondback rattlesnake (Crotalus adamanteus), longleaf pine stumps are commonly removed and harvested for rosin, eliminating associated underground habitats. We used trail cameras to examine the use of stump holes by vertebrates from September 2018 – May 2019. Each of 35 stump holes was paired with a nearby gopher tortoise burrow, a documented high value refugium type, to serve as a reference. We used Shannon Diversity Index to investigate species diversity differences and non-metric multidimensional scaling to investigate species composition differences between stump holes and tortoise burrows. We developed multi-season occupancy models to investigate reptile, amphibian, bird, and small mammal occupancy differences between tortoise burrows and stump holes. We documented 13 taxa unique to stump holes, 14 taxa unique to tortoise burrows, and 26 shared taxa. Although overall species diversity was similar between tortoise burrows and stump holes, species composition differed, with more reptile species associated with stump holes and more bird species associated with gopher tortoise burrows. Reptile, amphibian, bird, and small mammal occupancy was similar between stump holes and tortoise burrows and among stumps of varying decay states. Our research underscores the collective importance of tortoise burrows and stump holes as refugia and foraging sites for wildlife in the longleaf pine ecosystem. Additionally, our study demonstrates the importance of developing best management practices for stump removal such as retaining a proportion of stumps of different decay classes.

Woody biomass extraction for use as a feedstock for renewable energy may remove woody debris that provides suitable micro-climates for amphibians. We examined habitat use of the southern toad (Anaxyrus terrestris) as an indicator of relationships between amphibians and woody biomass in pine plantations of the southeastern United States using a controlled enclosure experiment and a field-based radio-telemetry study. In the enclosure experiment, we recorded toad selection among four 16-m2 treatments that varied in area of ground surface covered by coarse woody debris (CWD) and spatial allocation of CWD. Treatments were: (1) ≈100% of the ground area covered by CWD in one large pile (volume of CWD = 1.10 m3, 100CWD); (2) ≈50% of the ground area covered with CWD in one large pile (volume of CWD = 0.60 m3, 50PILE); (3) ≈50% of the ground area covered with CWD dispersed throughout the treatment (volume of CWD = 0.25 m3, 50DISP); and (4) no CWD (0CWD). In the radio-telemetry study, we identified southern toad daytime refuge locations and compared habitat characteristics to paired random locations. From May to August 2013, toads (n = 47) did not use enclosure treatments randomly during nocturnal hours (P

Neotoma floridana smalli (Key Largo Woodrat) is currently at high risk of extinction from anthropogenic disturbances, including loss and degradation of habitat and non-native predators. Habitat degradation may affect food-resource availability, yet food habits are poorly understood. Therefore, we examined seasonal diets of Key Largo Woodrats using microhistological analysis of fecal samples. We collected fecal material from captured individuals between January 2005 and February 2006 and identified food items to the lowest possible taxon. We classified food items as leaves, fruit, and insects to examine differences in diets between seasons (wet versus dry) and sexes. Fruit and leaves made up a greater percentage of Key Largo Woodrat diets during the wet and dry seasons, respectively, likely reflecting higher fruit availability during the wet season. Across seasons, diets of males had a higher percentage of fruit and insects, but a lower percentage of leaves than females. Greater fruit consumption ...

Loggerhead sea turtle (Caretta caretta) nesting-beach management is an integral component of population recovery efforts for this internationally threatened species. In Georgia, nests threatened by tidal inundation are commonly relocated to elevated dunes, and screens are placed over nests to prevent depredation. The objective of this study was to examine the effects of nest relocation and nest screening on both hatching success (proportion of successfully hatched eggs) and emergence success (proportion of hatchlings successfully emerging from the egg chamber) at Sapelo Island, Georgia. Results suggest that high hatching and emergence success rates can be maintained on Sapelo Island without nest relocation. Predator screens do not appear to affect hatching or emergence success and should continue to be used to protect nests from depredation.

The ability to fully evaluate potential relationships between forest management and bats is limited without information from relevant spatial scales. Further, knowledge of bat ecology in intensively managed forests is fairly limited even though these forests are a substantial portion of the forested landscape in the southeastern U.S. Therefore, we used occupancy models to examine influence of small-scale vegetation characteristics and large-scale spatial features on foraging patterns of bats within 6 managed-pine (Pinus spp.) forest landscapes in the southeastern U.S. Coastal Plain. We conducted repeated acoustic surveys to determine species presence/non-detection and evaluated a priori models relating detection probability and occupancy to site- and landscape-level metrics for 6 species/genera. Detection of big brown (Eptesicus fuscus) and eastern red (Lasiurus borealis)/Seminole (L. seminolus) bats (eastern red and Seminole bats combined) decreased with increasing basal area, and detection of big brown and Brazilian free-tailed bats (Tadarida brasiliensis) increased over the summer sampling period. Relationships between occupancy and habitat metrics were species-specific but consistent with previous studies. Occupancy for most bat species was lower at sampling sites with higher vegetation clutter and higher basal area. In contrast to most previous studies, occupancy of all bat species investigated was unrelated to or negatively influenced by distance to water. Although site- and landscape-level features influenced occupancy, our results indicate that site-specific features (vegetation clutter and basal area) influenced most species. Therefore, stand-level management activities that decrease vegetation structure, such as thinning intermediate-aged stands and/or controlling midstory vegetation (e.g., fire or herbicide applications), likely will maintain or increase suitability of managed pine forest stands and landscapes for many bat species in the southeastern Coastal Plain. The forest mosaics that we sampled, consisting primarily of managed pine stands intermingled with non-production habitat types, supported a large proportion of the bat community associated with forests of the Coastal Plain which suggests the compatibility of timber production and bat conservation objectives.

Shrews are integral components of forest food webs and may rely on downed woody debris to provide microhabitats that satisfy high moisture and metabolic requirements. However, woody biomass harvests glean downed woody debris to use as a bioenergy feedstock. Biomass Harvesting Guidelines (BHGs) provide guidance on the amount and distribution of downed woody debris retained after harvest to ensure ecological sustainability of woody biomass harvesting and limit detrimental effects on wildlife. However, the success of Biomass Harvesting Guidelines at reaching sustainability goals, including conservation of wildlife habitat, has not been tested in an operational setting. Thus, we compared shrew captures among six woody biomass harvesting treatments in pine plantations in North Carolina, USA from April to August 2011–2014 (n = 4) and Georgia, USA from April to August 2011–2013 (n = 4). Treatments included: (1) woody biomass harvest with no BHGs; (2) 15% retention with woody biomass dispersed; (3) 15% retention with woody biomass clustered; (4) 30% retention with woody biomass dispersed; (5) 30% retention with woody biomass clustered; and (6) no woody biomass harvested. We sampled shrews with drift fence arrays and compared relative abundance of shrews among treatments using analysis of variance. Additionally, we used general linear regression models to evaluate the influence of downed woody debris volume and vegetation structure on shrew capture success at each drift fence for species with >100 captures/state/year. In 53,690 trap nights, we had 1,712 shrew captures representing three species, Cryptotis parva, Blarina carolinensis, and Sorex longirostris. We did not detect consistent differences in shrew relative abundance among woody biomass harvest treatments, but relative abundance of all species increased over time as vegetation became established. In North Carolina, total shrew capture success was negatively related to volume of downed woody debris within 50 m of the drift fence array (P = 0.05) in 2013 and positively related to bare groundcover in 2013 (P = 0.02) and 2014 (P

Human induced land-use change in the form of urbanization and agriculture are rapidly transforming our planet’s terrestrial landscapes and causing the loss of species at unprecedented rates. Studies documenting the impacts of development are extensive; however, less is known about the scale at which species respond to development and specific features of altered landscapes that make them vulnerable. This shortcoming may be due to the difficulty of collecting data across large spatial extents, but filling these information gaps are critical, particularly for species that have a disproportionate influence on ecosystems, such as ecosystem engineers. One such species, the southeastern pocket gopher (Geomys pinetis), has been declining throughout its range (southeastern United States) and continued loss will likely have strong effects on the imperiled longleaf pine ecosystem in which it is closely associated. Using range-wide data from presence-absence surveys and publicly available presence-only data, we used recent advances in species distribution modeling to understand this ecosystem engineer’s associations with extensive land use and cover changes. Our study showed that pocket gophers inhabit a variety of land-use types, including regions with low levels of anthropogenic development, but are largely absent from intensely urbanized areas and closed-canopy forests. Conservation planning to reduce the spread of extensive development and forest management strategies to reduce closed-canopy systems will be instrumental in reducing the decline of the species and ultimately protection of the longleaf pine ecosystem. The approach used in this study will be increasingly beneficial for understanding species response to land-use change.

Geomys pinetis (Southeastern Pocket Gopher) is absent from much of its historic distribution due to reductions in suitable habitat, which consists largely of open Pinus (pine) systems. Restored open pine habitat represents an opportunity to reestablish Southeastern Pocket Gophers into areas within their historic distribution through translocation. Using radio telemetry, we documented evidence of avian predation on experimentally translocated Southeastern Pocket Gophers and no predation on non-translocated individuals. Translocated individuals exhibited greater movement rates, including aboveground movements, likely exposing them to increased predation risk.

Despite the importance of winter roosts to bat ecology, much less is known about tree roosts used by bats in winter than in summer. Rafinesque's big-eared bat (Corynorhinus rafinesquii) and southeastern myotis (Myotis austroriparius) are species of concern whose winter tree roost selection may be constrained by seasonal flooding in cypress-gum swamps. To evaluate winter roost selection by these species, we compared characteristics of winter roosts to trees not occupied in winter and to summer roost trees in the Oconee River floodplain, Laurens County, Georgia. We located 23 Rafinesque's big-eared bat winter roosts and 5 southeastern myotis winter roosts by climbing and visually inspecting hollow trees and by radio telemetry. We analyzed differences between used and unused trees in winter and between winter and summer roosts. Despite extensive flooding in winter, Rafinesque's big-eared bats roosted in cypress-gum swamps in summer and winter. Accordingly, they used similar large hollow water tupelo...

Roost characteristics have been described for most North American bats, but debate continues over the ultimate mechanisms behind roost selection. Hypotheses include the need for a stable microclimate, protection from predators, proximity to foraging habitat, and availability of alternative roosts, among others. Our objective was to weigh evidence for hypotheses regarding selection of diurnal summer roosts using southeastern myotis (Myotis austroriparius) as a model. We used transect searches and radiotelemetry to locate 25 roosts at eight study sites across the Coastal Plain of Georgia, USA. We measured 22 characteristics of trees, at all occupied roosts and at randomly selected unoccupied trees. We evaluated 10 hypotheses using single-season occupancy models. The best supported model predicted bat presence based on the variables tree species, solid wood volume, and canopy cover. Because these characters affect heat retention and insolation, our results are consistent with the hypothesis that bats select ...

Declines of imperiled small mammals are often attributed to predation without investigating the relative influence of survival and reproductive parameters on population growth. Accordingly, declines in the endangered Key Largo woodrat Neotoma floridana smalli (KLWR) population have been attributed to predation by feral cats Felis catus, Burmese pythons Python molurus bivittatus and raccoons Procyon lotor. We estimated survival, recruitment and realized population growth rates from four capture‐mark‐recapture studies to determine if the pattern of demographic variation was consistent with predation as the primary cause of KLWR declines. Additionally, we evaluated the KLWR captive-breeding and release program by comparing survival of captive-born and released KLWRs to wild-born KLWRs. The realized population growth rate of wild-born KLWRs had a strong pattern of covariation with recruitment; covariation between the realized population growth rate and apparent survival was negligible. Consistent with demographic theory, our results suggest that KLWR population dynamics were driven primarily by variation in recruitment, and that periodic reductions in recruitment led to population declines. We found that the survival curve and the first month (S1) and first 3-month (S1‐3) survival estimates for the wild-born KLWRs [S1 = 0.929 (0.890‐0.968); S1‐3 = 0.942 (0.919‐0.965)] were considerably higher (c 2 = 33.9, 1 d.f., P < 0.001) than released KLWRs [S1 = 0.521 (0.442‐0.600); S1‐3 = 0.561 (0.493‐0.629)]. Low survival rates from predation limited the success of the captive-breeding and release program. This study illustrates the importance of pre-release conditioning of captive-bred animals and the importance of considering reproductive parameters in conjunction with survival estimates to understand the drivers of population decline.

Recovery of loggerhead turtle Caretta caretta populations depends on many factors, including reducing anthropogenic mortality of adult turtles. Shrimp trawls are considered a major source of mortality for adult loggerhead turtles despite the mandatory use of turtle excluder devices. We modeled scenarios for reducing the likelihood of interaction between nesting adult loggerhead turtles and shrimp trawlers operating off the coast of Georgia during the nesting season (May–August). We used satellite telemetry and aerial surveys to describe the distribution patterns of nesting adult female turtles (2004–2005; n = 22) and shrimp trawls (1999–2005), respectively, across waters adjacent to the Georgia shoreline. Adult female turtles and shrimp trawlers both occupied state waters extensively during the nesting season. Turtles tended to have long, narrow home ranges that were located parallel to shore and that overlapped with the shrimp trawl distribution, which showed a slight grouping around deep channe...

Forests are a major supplier of renewable energy; however, gleaning logging residues for use as woody biomass feedstock could negatively alter habitat for species dependent on downed wood. Biomass Harvesting Guidelines (BHGs) recommend retaining a portion of woody biomass on the forest floor following harvest. Despite BHGs being developed to help ensure ecological sustainability, their contribution to biodiversity has not been evaluated experimentally at operational scales. We compared herpetofauanal evenness, diversity, and richness and abundance of Anaxyrus terrestris and Gastrophryne carolinensis among six treatments that varied in volume and spatial arrangement of woody biomass retained after clearcutting loblolly pine (Pinus taeda) plantations in North Carolina, USA (n = 4), 2011-2014 and Georgia (n = 4), USA 2011-2013. Treatments were: (1) biomass harvest with no BHGs, (2) 15% retention with biomass clustered, (3) 15% retention with biomass dispersed, (4) 30% retention with biomass clustered, (5) 30% retention with biomass dispersed, and (6) no biomass harvest. We captured individuals with drift fence arrays and compared evenness, diversity, and richness metrics among treatments with repeated-measure, linear mixed-effects models. We determined predictors of A. terrestris and G. carolinensis abundances using a priori candidate N-mixture models with woody biomass volume, vegetation structure, and groundcover composition as covariates. We had 206 captures of 25 reptile species and 8710 captures of 17 amphibian species during 53690 trap nights. Herpetofauna diversity, evenness, and richness were similar among treatments. A. terrestris abundance was negatively related to volume of retained woody biomass in treatment units in North Carolina in 2013. G. carolinensis abundance was positively related with volume of retained woody debris in treatment units in Georgia in 2012. Other relationships between A. terrestris and G. carolinensis abundances and habitat metrics were weak or absent. The lack of consistent community or population responses suggests the addition of a woody biomass harvest to a clearcut in pine plantations does not impact herpetofauna use of Coastal Plain loblolly plantations in the southeastern United States. We recommend additional research to examine relationships between woody biomass harvesting and rarer species or amphibians with high desiccation risk, particularly in other regions and harvesting systems.

Roost requirements of most North American forest bats are well-documented, but questions remain regarding the ultimate mechanisms underlying roost selection. Hypotheses regarding roost selection include provision of a stable microclimate, space for large colonies, protection from predators, and proximity to foraging habitat, among others. Although several hypotheses have been proposed, specific mechanisms likely vary by species and geographic region. Rafinesque's big-eared bat (Corynorhinus rafinesquii) commonly roosts in trees with large basal hollows in the Coastal Plain of the southeastern United States. Our objective was to weigh evidence for hypotheses regarding selection of diurnal summer roosts by Rafinesque's big-eared bat at 8 study sites across the Coastal Plain of Georgia, USA. We used transect searches and radiotelemetry to locate roosts and measured 22 characteristics of trees, tree cavities, and surrounding vegetation at all occupied roosts and for randomly selected unoccupied trees. We evaluated 10 hypotheses using single-season occupancy models and used Akaike's information criterion to select the most parsimonious models. We located 170 tree roosts containing approximately 870 bats for our analysis. The best supported model predicted bat presence from cavity size, interior wall texture, and number of entrances. Because large cavities allow bats to fly and smooth walls impede attacks by terrestrial predators, our results are consistent with the hypothesis that bats select roosts that allow them to evade predators. However, data on predation rates are needed for a conclusive determination. Because trees suitable as roosts for Rafinesque's big-eared bat are rare in the landscape, protection of suitable forested wetland habitat is essential to provide current and long-term roost tree availability. © 2012 The Wildlife Society.

It is widely assumed that tree cavity structure and microclimate affect cavity selection and use in cavity-dwelling bats and birds. Despite the interest in tree structure and microclimate, the relationship between the two has rarely been quantified. Currently available data often comes from artificial structures that may not accurately represent conditions in natural cavities. We collected data on tree cavity structure and microclimate from 45 trees in five cypress-gum swamps in the Coastal Plain of Georgia in the United States in 2008. We used hierarchical linear models to predict cavity microclimate from tree structure and ambient temperature and humidity, and used Aikaike's information criterion to select the most parsimonious models. We found large differences in microclimate among trees, but tree structure variables explained28% of the variation, while ambient conditions explained80% of variation common to all trees. We argue that the determinants of microclimate are complex and multidimensional, and therefore cavity microclimate cannot be deduced easily from simple tree structures. Furthermore, we found that daily fluctuations in ambient conditions strongly affect microclimate, indicating that greater weather fluctuations will cause greater differences among tree cavities.