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Population genetic diversity is widely accepted as important to the conservation and management of wildlife. However, habitat features may differentially affect evolutionary processes that facilitate population genetic diversity among sympatric species. We measured genetic diversity for two pond-breeding amphibian species (Dwarf salamanders, Eurycea quadridigitata; and Southern Leopard frogs, Lithobates sphenocephalus) to understand how habitat characteristics and spatial scale affect genetic diversity across a landscape. Samples were collected from wetlands on a longleaf pine reserve in Georgia. We genotyped microsatellite loci for both species to assess population structures and determine which habitat features were most closely associated with observed heterozygosity and rarefied allelic richness. Both species exhibited significant population genetic structure; however, structure in Southern Leopard frogs was driven primarily by one outlier site. Dwarf salamander allelic richness was greater at sites with less surrounding road area within 0.5 km and more wetland area within 1.0 and 2.5 km, and heterozygosity was greater at sites with more wetland area within 0.5 km. In contrast, neither measure of Southern Leopard frog genetic diversity was associated with any habitat features at any scale we evaluated. Genetic diversity in the Dwarf salamander was strongly associated with land cover variables up to 2.5 km away from breeding wetlands, and/or results suggest that minimizing roads in wetland buffers may be beneficial to the maintenance of population genetic diversity. This study suggests that patterns of genetic differentiation and genetic diversity have associations with different habitat features across different spatial scales for two syntopic pond-breeding amphibian species. [ABSTRACT FROM AUTHOR]

We examined spatial ecology and habitat use of Coluber flagellum (Coachwhip) in a 12,000-ha Pinus palustris (Longleaf Pine) reserve in southwestern Georgia from 2007 through 2008. We radio-tracked 7 Coachwhips (5 males and 2 females) for 291 to 325 days. The average 100% minimum convex polygon (MCP) home-range for all snakes was 102.9 ± 28 ha. Daily movement during the active season (April–November) varied from 28.6 to 73.6 m for males (n = 5) and from 27.5 to 95.6 m for females (n = 2). Snakes were usually associated with open-canopied pine forests and found less often in aquatic and agricultural habitats. Our results are consistent with evidence from previous studies in that Coachwhips used sites with open-forest structure and large expanses of habitat. [ABSTRACT FROM AUTHOR]

Six-lined racerunner ( Aspidoscelis sexlineata) is an indicator species of frequently burned Longleaf pine ( Pinus palustris) forests. To evaluate how the species responded to forest restoration, we conducted a mark-recapture study in formerly fire-suppressed Longleaf pine forests exposed to prescribed fire or fire surrogates (i.e. mechanical or herbicide-facilitated hardwood removal) as well as in fire-suppressed control sites and reference sites, which represented the historic condition. After initial treatment, all sites were exposed to over a decade of prescribed burning with an average return interval of approximately 2 years. We used population-level response of A. sexlineata as an indicator of the effectiveness of the different treatments in restoring habitat. Specifically, we compared mean numbers of marked adults and juveniles at treatment sites to that of reference sites. After 4 years, restoration objectives were met at sites treated with burning alone and at sites treated with mechanical removal of hardwoods followed by fire. After over 10 years of prescribed burning, restoration objectives were met at all treatments. We conclude that prescribed burning alone was sufficient to restore fire-suppressed Longleaf pine sandhills for A. sexlineata populations. [ABSTRACT FROM AUTHOR]

Measuring the effects of ecological restoration on wildlife assemblages requires study on broad temporal and spatial scales. Longleaf pine (Pinus palustris) forests are imperiled due to fire suppression and subsequent invasion by hardwood trees. We employed a landscape‐scale, randomized‐block design to identify how reptile assemblages initially responded to restoration treatments including removal of hardwood trees via mechanical methods (felling and girdling), application of herbicides, or prescribed burning alone. Then, we examined reptile assemblages after all sites experienced more than a decade of prescribed burning at two‐ to thee‐year return intervals. Data were collected concurrently at reference sites chosen to represent target conditions for restoration. Reptile assemblages changed most rapidly in response to prescribed burning, but reptile assemblages at all sites, including reference sites, were generally indistinguishable by the end of the study. Thus, we suggest that prescribed burning in longleaf pine forests over long time periods is an effective strategy for restoring reptile assemblages to the reference condition. Application of herbicides or mechanical removal of hardwood trees provided no apparent benefit to reptiles beyond what was achieved by prescribed fire alone. [ABSTRACT FROM AUTHOR]

Recent reports of declines in terrestrial snake populations in the southeastern U.S. have highlighted the need for life history information for these often cryptic animals. In this study, we used radio-telemetry to describe home range size and habitat use of the Florida Pine Snake (Pituophis melanoleucus mugitus), a large fossorial species associated with the endangered Longleaf Pine (Pinus palustris) ecosystem. Florida Pine Snakes had large home ranges that varied in size among individuals (mean = 59.2 ± 50.8 ha, minimum convex polygon). There was no significant difference between mean annual home range size of males and females, but home range size differed significantly among seasons and between males and females by season. At the home range scale, Florida Pine Snakes selected natural pine forests and mature slash pine plantations, and they tended to use sites with shrubs and vines and very little bare ground at a local scale. As has been observed in other studies, Florida Pine Snakes were highly fossorial and they frequently sought shelter in Southeastern Pocket Gopher (Geomys pinetus) burrows. Snakes in our study rarely crossed paved or graded dirt roads; however, they frequently crossed low-use harrowed dirt roads. Collectively, our findings indicate that Florida Pine Snakes require large contiguous pine forests and that paved and graded roads may be significant barriers to their movement. [ABSTRACT FROM AUTHOR]

In colder climates, survival of neonate Timber Rattlesnakes (Crotalus horridus) following dispersal relies heavily on conspecific scent trailing and the ability to locate suitable communal hibernacula. Less is known regarding populations in the southern portion of their range where they are more likely to den solitarily in ephemeral overwintering sites. On 6 August 2009, we captured a post-parturient female Timber Rattlesnake with a litter of 23 neonates in a hardwood thicket within a Longleaf Pine (Pinus palustris) forest in southwestern Georgia. Fourteen of the neonates were radio-tracked to examine their movements and activity range overlap as they dispersed from the natal site. Snakes were tracked for periods of 1-110 days, daily for the first three weeks and at least three times per week thereafter. Dispersal distances increased over time, and overlap of activity ranges was minimal, potentially reducing intraspecific competition between litter mates. Neonates were located predominantly beneath clumps of vegetation or beside coarse woody debris (62.4%), in hardwood tree branches (31.6%), or just off the ground in vegetation or on top of course woody debris (6.0%). Selection of appropriate cover structure may aid in reducing susceptibility to predation. [ABSTRACT FROM AUTHOR]

Less than 4% of the once extensive Pinus palustris (longleaf pine) ecosystem remains today. Although longleaf pine habitats are recognized for their high species diversity, few published accounts document the vertebrate faunas of remaining tracts. Here we report on the vertebrate species richness of Ichauway, an 11,300-ha property in Baker County, GA. The property includes ca. 7300 ha of longleaf pine with native ground cover, along with more than 30 seasonal wetlands and ca. 45 km of riparian habitat associated with Ichawaynochaway Creek, Big Cypress Creek, and the Flint River. The fauna includes 61 species of fish, 31 amphibians, 53 reptiles, 191 birds, and 41 mammals. Despite the relative isolation of the property from other natural ecosystems, the vertebrate fauna of Ichauway is remarkably diverse and may offer an example of reference conditions to guide restoration of longleaf pine forests, associated seasonal wetlands, and riparian areas elsewhere in the southeastern US. [ABSTRACT FROM AUTHOR]

• 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]