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Gopher Tortoise ( Gopherus polyphemus) burrows are used by more than 60 vertebrate species, but the frequency with which species use burrows and the extent to which other vertebrates use the mound of sand at the burrow entrance, called the burrow apron, has not been quantitatively assessed. Between 2 June and 9 October 2014, we monitored active and inactive adult Gopher Tortoise burrows with motion-triggered trail cameras to identify and enumerate vertebrate burrow visitors. We recorded 12,238 video clips during 2299 trap nights, of which 10,151 (83%) contained a Gopher Tortoise and 1732 (14%) contained other vertebrate species. We reduced multiple videos of a single burrow visitation to 1 observation, resulting in 929 observations of 14 vertebrate species (not including the Gopher Tortoise) using tortoise burrows and 34 species on burrow aprons. Mammals were the most commonly recorded taxa (54%), followed by birds (32%), amphibians (9%), and reptiles (5%). Active burrows were visited more frequently than inactive burrows across all taxa, and burrow aprons were used more frequently than the burrow tunnel. Although active and inactive Gopher Tortoise burrows provide refuge for some vertebrate species, active burrows may provide additional resources, such as increased prey for insectivorous species. More species were found to be present on burrow aprons than within burrows, indicating the apron may be an important microhabitat for species, including those not known to use burrows. [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]

In the course of conducting a radio-telemetry study of Lampropeltis getula getula (Eastern Kingsnake) within a ca. 3000-ha area in southwestern Georgia, we observed that adjacent home ranges of individuals infrequently overlapped. To quantify this overlap, ten interactions were compared; male/female overlap averaged 25%, while male/male overlap averaged 13%. Although we lack corroborative data, the limited overlap we observed is consistent with what would be expected from a territorial animal. [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]

To assess use of terrestrial habitat by ambystomatid salamanders, Ambystoma tigrinum (Tiger Salamanders) were monitored with radiotelemetry. Four individuals were tracked as they exited a wetland and made wide use of the surrounding landscape. Salamanders moved up to 255 m from the wetland of origin and found refugia both within forested land and wildlife food plots. Based on the extent of terrestrial movements by Tiger Salamanders, our findings support previous work demonstrating that upland habitat surrounding wetlands are critical areas in amphibian life cycles. Salamander movements did not appear to be influenced by agricultural development, as two individuals traveled through this habitat type. [ABSTRACT FROM AUTHOR]

Animals live in complex environments that vary spatially and temporally. This heterogeneity strongly influences the availability and quality of food resources and has strong impacts on growth and survival of consumers. Geographically isolated wetlands provide an interesting system to study trophic relationships because they vary spatially and temporally in hydrology and vegetation. Larval anurans play an important role in these wetland systems because they are often the most abundant consumers. Yet, little is known about larval anuran diet. Here we assessed the diet of 3 larval anurans ( Acris gryllus [Southern Cricket Frog], Hyla gratiosa [Barking Treefrog], and Lithobates sphenocephalus [Southern Leopard Frog]), across 2 isolated wetland types (marsh and cypress savanna) using a stable isotope mixing model, stable isotope analysis in R (SIAR). Furthermore, we assessed variation in basal resource and anuran tissue stoichiometry (C:N). Our analyses suggested that larvae of these 3 species primarily function as herbivores and detritivores. All fed on a mix of algal resources, detrital particulate organic matter, and litter originating from the wetland canopy. Barking Treefrog had a lower C:N than the other two species, suggesting their dietary N requirements may be greater. Understanding the trophic roles of these animals is essential in determining their ecological significance and contributes to a more complete view of isolated wetlands in the surrounding landscape. [ABSTRACT FROM AUTHOR]

Macrochelys temminckii (Alligator Snapping Turtle) was petitioned for federal listing as threatened under the Endangered Species Act in 2012 as a result of population declines attributable in part to harvest for human consumption. The species was listed as threatened in 1992 in Georgia, where all harvest of the species was closed. Because little is known about how Alligator Snapping Turtle populations respond to protection, we surveyed Georgia's Flint River, which had originally been surveyed in 1989, to assess whether abundance of Alligator Snapping Turtles increased following close of commercial harvest. Our survey, conducted in 2014 and 2015 yielded captures of 52 Alligator Snapping Turtles with an overall catch per unit effort (CPUE) of 0.09 turtles/trap-night, as compared to 62 captures and a CPUE of 0.08 turtles/trap-night in the 1989 survey. Although CPUE was similar between the two studies, we observed differences among the lower, middle, and upper reaches of the river; CPUE increased in the lower reach, decreased slightly in the middle reach, and remained the same in the upper reach of the Flint River. Mean size (carapace length) of Alligator Snapping Turtles did not differ between the 2 surveys, but in 2014-2015 we caught nearly twice as many immature (<40 cm carapace length) turtles as adult males and females, and the highest proportion of immature turtles was captured in the upper reach. Our findings suggest that the Alligator Snapping Turtle population in the Flint River has not increased despite 22 years of protection from commercial harvest. Recovery may be hampered by life-history characteristics of the species including delayed maturity and low reproductive output; however, we cannot rule out possible ongoing mortality of Alligator Snapping Turtles from illegal harvest or drowning on abandoned limb lines, as has been observed in other populations. [ABSTRACT FROM AUTHOR]

We sampled five stream reaches within an agricultural landscape in southwestern Georgia fur benthic macroinvertebrates and larval amphibians from 2002 to 2003 to determine whether cattle grazing impacts these Faunal components. Two of the stream reaches had been fenced to exclude cattle (buffered), whereas the other three were not, allowing cattle access to the streams (unbuffered). We captured larval Eurycea cirrgera (Southern Two-lined Salamanders) incidentally in our benthic samples and compared salamander capture rates between buffered versus unbuffered streams. We also examined salamander stomach contents relative to the composition and abundance of benthic macroinvertebrates, comparing these data by stream type as well. Overall, capture success for larval salamanders was higher at buffered sites. Midge larvae (family Chironomidae) were the most frequent invertebrate taxon detected, both in the benthic and stomach content samples; however, we also observed cladocerans, copepods, and ostracods in each sampling regime. A linear electivity index revealed that larval Southern Two-lined Salamanders showed slight dietary selection for midge larvae in the subfamily Tanypodinae. This finding, coupled with the observation that chironomid larvae composed over half of Southern Two-lined Salamanders stomach contents, suggests some preference or selection for this benthic group. However, larval Tanypodinae were found at all sites, suggesting that their identification to species level may be necessary to determine whether differences in the prey base explained differences in salamander selectivity between buffered versus unbuffered streams. Factors other than prey selectivity, such as instream habitat quality, may also have influenced larval salamander abundance. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The reproductive ecology of male Crotalus adamanteus Beauvois (Eastern Diamond-backed Rattlesnake) from southwestern Georgia (Joseph W. Jones Ecological Research Center, Baker County) was studied from 14 August 2003 to 14 August 2006. Few studies provide information on reproduction of free-living Eastern Diamond-backed Rattlesnakes, and no information is available on the seasonal relationship of plasma sex steroids of males to changes in the reproductive organs (e.g., mass of the testis and kidney) and the mating season. Here, the main goals were to determine whether: (i) males show variation in concentrations of plasma testosterone (T) during the active season (late March through November), (ii) males have elevated (peak) concentrations of plasma T during the single mating season, which has been documented to occur from late summer through early fall in nearby populations, and (iii) there are seasonal changes in length, width, and mass of the testis and kidney during the active season, particularly during the breeding period. There was a significant difference in mean concentrations of plasma T among seasons, with levels in summer significantly greater than those of spring, and levels in spring and fall were not significantly different. Testis mass and width, but not length, varied significantly across seasons. Testis mass paralleled elevated levels of plasma T, with peak mass occurring in the summer. Similarly, testis width was significantly greater in summer than in fall, but there was no significant difference between summer and spring, nor between spring and fall. We found no significant seasonal changes in any of the kidney measurements. Bisexual pairings were coincident or followed the occurrence of elevated levels of plasma T and changes in testis size; however, despite frequent observations, copulations were not observed. Nonetheless, our results support a mating season of late summer/early fall for the present population of Eastern Diamond-backed Rattlesnakes. [ABSTRACT FROM AUTHOR]