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Highlights • Open pine woodlands provide habitat for a suite of wildlife species of concern. • Existing guidelines for vegetation structure to benefit these species were tested. • We used wildlife data for 17 species to develop models for comparison to guidelines. • Existing guidelines for herbaceous and canopy cover could be expanded. • Expanded guidelines increase management flexibility while still benefitting wildlife. Abstract Open pine ecosystems of the southern United States are a conservation priority for many agencies, organizations, and private landowners. These woodlands, characterized by moderately-stocked overstories, low cover of midstory, and grass-dominated herbaceous groundcover, provide important habitat for a suite of rare and declining wildlife species. To provide guidance for land managers engaged in habitat restoration in open pine ecosystems, ranges of desired conditions for elements of vegetation structure have been developed using literature survey and expert opinion. We compared empirical data on habitat occupancy for 17 wildlife species from second-growth longleaf pine woodlands in southwestern Georgia with recommended ranges for basal area (BA) of all pine, BA of pine ≥ 35.5 cm dbh, percent canopy cover, percent herbaceous cover, and percent shrub cover. Vegetation data were taken from 864 monitoring plots and Mahalanobis distance models were used to develop habitat suitability indices from the wildlife data. Recommendations for shrub cover and BA of pines ≥ 35.5 cm fit well with model predictions for all wildlife species. However, mean BA of all pines at sites used by wildlife were at the low end of the recommended range. Herbaceous cover at sites used by wildlife was well below the recommended range, whereas canopy cover was well above recommendations, suggesting these ranges should be expanded. These modifications could provide managers of open pine ecosystems greater flexibility, allowing them to incorporate a broader suite of objectives in their management while still providing habitat for wildlife species of concern. Moreover, our models suggest that monitoring presence of open pine indicator bird species may be an efficient method to assess restoration or management progress of open canopy pine systems. [ABSTRACT FROM AUTHOR]

Highlights • Ichauway snakes' home ranges were at least 2.6 times larger than other sites. • Snakes at all sites selected open edge and pine habitat at the landscape scale. • Snakes at all sites were most likely found in large, mature oak trees. • Hardwood removal activities may have limited suitable trees that rat snakes use. Abstract An animal's spatial ecology may provide insight into how resources are distributed or potentially limiting across its home range. Some species with broad geographic distributions may exhibit intraspecific variation in space use among populations given the spectrum of available habitat across their range. Animals may need to move further in habitats with limited resources thereby lowering survival. Species, like the eastern rat snake (Pantherophis alleghaniensis), occur throughout the eastern USA and are thought to be strongly tied to hardwood forests. However, their occurrence in pine-dominated forests in the southeastern USA suggests they have broader habitat requirements than previously noted. Our objective was to investigate patterns of habitat use and spatial ecology for eastern rat snakes across multiple pine-dominated forests in Southern Georgia and Northern Florida to capture regional differences in eastern rat snake resource use. We examined home range and habitat use at multiple spatial scales for 30 radio-telemetered snakes from three sites; one in Georgia (Pebble Hill) and Florida (Tall Timbers) during 2004–2005 and one more northern site in Georgia (Ichauway) during 2010–2012. Snakes tracked on Ichauway had a mean home range size that was 3.9 times larger (95% Mean Convex Polygon [MCP], 13.6 ± 8.2 ha) than the estimate for Tall Timbers (3.5 ± 3.2 ha) and 2.6 times larger than the estimate for Pebble Hill (5.3 ± 3.2 ha). Snakes at all three sites selected primarily open edge and pine habitat at the landscape scale and were most likely to be found in large, mature oak trees (Quercus spp.). At Ichauway, hardwood removal activities associated with longleaf pine (Pinus palustris) restoration reduced the number of hardwood trees per hectare by 33% in hardwood removal areas from 1998 to 2014. This management approach included limiting suitable large oak trees that rat snakes use and may help explain the variation in home range size and the number of snakes captured at Ichauway (n = 14) compared to the other two sites (Tall Timbers, n = 154, Pebble Hill, n = 127). [ABSTRACT FROM AUTHOR]

Abstract: Globally, there is a growing awareness that geographically isolated wetlands contribute to important landscape functions and ecological services. One of their most important functions is providing habitat to a diverse fauna and flora adapted to variable wet and dry environments. We focus on analysis of similarities among three distinct taxa, vascular plants, aquatic beetles, and amphibians, in isolated wetlands in the southeastern coastal plain of Georgia. Although species richness for these three taxa is quite high in isolated wetlands at a regional scale, we found a low degree of congruence in species richness and species composition among taxa. This finding demonstrates that none of these groups could be used as a surrogate for the overall biodiversity of these wetlands represented by the three taxa. We identified environmental factors influencing the complex patterns of species richness and distribution for the three groups that indicate biotic and abiotic processes operate at different scales for each taxonomic group and for individual species. Our study illustrates the importance of considering structural diversity, hydrologic variation, and landscape position as key elements to understanding overall diversity represented by the three taxa in isolated wetlands and in developing assessment tools of wetland condition. [Copyright &y& Elsevier]

We developed an interactive management model for wild and captive populations of the ploughshare tortoise or angonoka, Geochelone yniphora. Interactive management is based on the translocation of individuals between wild and captive populations to simulate a metapopulation. Demographic parameters of one captive and two wild populations of this rare tortoise were used to conduct a metapopulation viability analysis (MVA). The effectiveness of the conservation strategy proposed for this species was then evaluated by modifying the probability of extinction and growth of the metapopulation over a fixed period of time. Several alternative scenarios of interactive management were then tested and ranked in terms of their effect on the viability of the metapopulation. The model predicted that catastrophic events such as bush fires would likely have a negative effect on the future of remaining wild populations. However, the model also predicted that the use of captive-born offspring to establish additional wild populations would decrease the risk of extinction of the metapopulation as a whole. We believe that, when supported by sound knowledge of the demographic parameters of a species, the use of MVA as part of an interactive management program can be an effective conservation tool that allows assessment of the probable response of both captive and wild populations to different management alternatives. One of the most interesting aspects of this interactive management approach is the link between in situ and ex situ conservation. [Copyright &y& Elsevier]

• Species diversity was similar, but species composition differed. • Vertebrate occupancy was similar between stump holes and tortoise burrows. • Results underscore the importance of both habitat features in this ecosystem. 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. [ABSTRACT FROM AUTHOR]

• Frequent fire benefits many snake species found within mesic longleaf pine forests. • Most snake species occupied areas that had been burned within two years. • Frequent fire may provide basking and refugia sites and more foraging opportunities. Prescribed fire is an essential tool for the restoration and maintenance of the longleaf pine (Pinus palustris) ecosystem. This type of management benefits wildlife species that are frequently associated with open canopy pine forests in the Southeastern U.S., including upland snakes. But few studies have examined the long term effects of prescribed fire (i.e., fire frequency over time) on snake occurrences at local and landscape scales. Likewise, comprehensive data are lacking on the response of snakes to individual prescribed burns (i.e., how long after a fire does a snake occupy a location). To investigate snake responses to these two factors, we used radio-telemetry data for five species of snakes, including three species of open-canopied forest specialists and two species that occur more broadly in upland forests (i.e., generalists), on a large site managed with prescribed fire. We hypothesized that open-canopied forest specialists, eastern diamondback rattlesnake (Crotalus adamanteus), Florida pine snake (Pituophis melanoleucus), and eastern coachwhip (Coluber flagellum) would select more frequently burned locations over less frequently burned locations and would occupy locations sooner after a fire than generalist species, eastern kingsnake (Lampropeltis getula) and gray ratsnake (Pantherophis allegheniensis). We used spatial data collected from previous snake radio-telemetry studies conducted over a nine year period (2003–2012) and annual burn data from 1994 to 2012. We used compositional analysis to evaluate snake use (selection) versus availability of locations based on fire frequency at different spatial scales (home range and landscape). As predicted, open-canopied forest specialists selected locations with more frequent fire (≤2.5 y return interval) significantly more often than locations with less frequent fire (≥3.3 y return interval; F 7, 18 = 9.06, p < 0.0001). Whereas habitat generalists selected locations with fires across a broader spectrum of frequencies (every 2–10 y) significantly more often than locations that were not burned in 10 years (no burn) or those burned most frequently (1.4 y return interval; F 7, 21 = 5.94, p < 0.001). The three open-canopied forest specialists, as well as the generalist, eastern kingsnake, predominantly used locations within two years after a burn (eastern diamondback rattlesnake, 81% of locations; Florida pine snake, 91% of locations; eastern coachwhip, 98% of locations; and eastern kingsnake, 91% of locations. The generalist, grayrat snake, selected locations where time since burn was less than two years (53.8% of locations), as well as, locations that had not been burned in 10 years (23.5%). Our data suggest that forest management programs that include prescribed fire with short burn return intervals (<3 y) over long time periods would benefit both open-canopied forest specialists and generalist snake species that use open-canopied forests. [ABSTRACT FROM AUTHOR]

Individual animals undergoing ontogenetic shifts in habitat use may establish a mobile link between discrete ecosystems via movement of energy, nutrients and matter, as well as through impacts on ecosystem and habitat structure. The American Alligator (Alligator mississippiensis) is a model species for studying ecological implications of ontogenetic niche shifts, because they grow in size by several orders of magnitude, and they play a critical role as both top predators and ecosystem engineers. We used equal trapping effort, radio telemetry and nest surveys to document ontogenetic habitat shifts of alligators between hydrologically isolated, seasonal wetlands and riverine systems. To estimate the degree of functional connectivity between systems, we quantified alligator biomass and nutrient excretion in both systems. Seasonal wetlands provided nesting and nursery sites for adult females and juveniles, which constituted 0.78g/m2 biomass and excreted 0.05g/m2/yr N, P, Ca, Mg, Na and K in that system. In contrast, the riverine system provided non-nesting habitat for adults and sub-adults of both sexes, totaling 0.18g/m2 biomass and excreting 0.01g/m2/yr of nutrients. Furthermore, sub-adults and adult females were documented moving across the terrestrial matrix, while adult males spent the duration of the study in the creek. Our results demonstrated that ontogenetic niche shifts in alligators establish connectivity between seasonal wetlands and riverine systems and with the surrounding terrestrial matrix. These findings have implications for the definition of jurisdictional wetlands under the US Supreme Court¿s 2001 SWANCC decision and highlight the importance of ecological, as well as hydrological, connectivity. [Copyright &y& Elsevier]

Because of high numbers of animals killed on Paynes Prairie State Preserve, Alachua County, Florida, the Florida Department of Transportation constructed a barrier wall-culvert system to reduce wildlife mortality yet allow for passage of some animals across the highway. During a one year study following construction, we counted only 158 animals, excluding hylid treefrogs, killed in the same area where 2411 road kills were recorded in the 12 months prior to the construction of the barrier wall-culvert system. Within the survey area lying directly in Paynes Prairie basin, mortality was reduced 65% if hylid treefrogs are included, and 93.5% with hylid treefrogs excluded. Sixty-four percent of the wildlife kills observed along the barrier wall-culvert system occurred at a maintenance road access point and along 300 m of type-A fence bordering private property. The 24 h kill rate during the post-construction survey was 4.9 compared with 13.5 during the pre-construction survey. We counted 1891 dead vertebrates within the entire area surveyed, including the ecotone between the surrounding uplands and prairie basin which did not include the barrier wall and culverts. Approximately 73% of the nonhylid road kills occurred in the 400 m section of road beyond the extent of the barrier wall-culvert system. We detected 51 vertebrate species, including 9 fish, using the 8 culverts after the construction of the barrier wall-culvert system, compared with 28 vertebrate species in the 4 existing culverts prior to construction. Capture success in culverts increased 10-fold from the pre-construction survey to the post-construction survey. Barrier wall trespass was facilitated by overhanging vegetation, maintenance road access, and by the use of the type-A fence. Additional problems resulted from siltation, water holes, and human access. These problems could be corrected using design modifications and by routine, periodic maintenance. [Copyright &y& Elsevier]

Abstract: The extinctions of keystone megafauna during the Pleistocene and Holocene continue to affect extant species and ecosystems. This is particularly acute in southern and western Madagascar where two now extinct species of giant tortoises were once amongst the most dominant herbivores. The extinct giant tortoises are likely to have influenced ecosystem processes by being effective dispersers of large seeds, keeping the understorey open, cycling nutrients, and indirectly regulating fire regimes. As a result of their extinction, ecological interactions and ecosystems have been altered. Given that there is evidence that the extant Aldabran giant tortoise, Aldabrachelys gigantea, is closely related to at least one of these Madagascan giant tortoises, Aldabrachelys abrupta, we propose using captive Aldabran giant tortoises to restore missing ecological functions. This ambitious approach will represent the first continental island restoration project with a surviving lineage of now extinct, endemic megafauna. Translocation of this megafauna species could be a pragmatic and cost-effective tool to contribute to halting the ongoing extinction processes in parts of western and southern Madagascar, and would further understanding of the role of these species in pre-human Madagascan ecosystems. [Copyright &y& Elsevier]