Southeastern Naturalist 529 C.K. Dodd, Jr. and W.J. Barichivich 22001177 SOUTHEASTERN NATURALIST 1V6o(4l.) :1562,9 N–5o4. 54 A Survey of the Amphibians of Savannah National Wildlife Refuge, South Carolina and Georgia C. Kenneth Dodd Jr. 1, 2,* and William J. Barichivich1 Abstract - From 2004 to 2006, we used a variety of sampling techniques to survey the amphibians of Savannah National Wildlife Refuge (SNWR), a large protected area straddling the lower portions of the Savannah River on the border between South Carolina and Georgia. We documented 22 amphibian species—15 frogs and 7 salamanders—with a possible 23rd species present. Species richness was lower than what might be expected from amphibian field guides of species inhabiting the adjacent Coastal Plain, likely due to a lack of specialized habitats, such as temporary ponds and upland pine forest. Amphibians occupied a variety of habitats and appeared tolerant of the mildly acidic and low-oxygen conditions of many of the wetlands. Although additional species may be found at SNWR, this initial survey provides a historic baseline for monitoring amphibian populations as areas adjacent to the refuge are disturbed, the climate changes, and multi-use management objectives are implemented within refuge boundaries. Introduction Although the Atlantic and Gulf Coastal Plains of southeastern North America contain a high diversity of amphibians (Dodd 1997, Duellman and Sweet 1999), information on species richness is unavailable, unpublished, or based on anecdotal information for many of the protected areas within this region. One of the first steps to understanding amphibian communities is to establish which species occur within a region. This knowledge is vitally important because amphibians play significant roles in ecosystem function, particularly as predators of invertebrates, prey for a vast array of other species, and in nutrient transfer to and from habitats rich in nutrients (e.g., ponds) to areas poor in nutrients, such as sandy uplands (Capps et al. 2014, Earl et al. 2011, Hocking and Babbitt 2014). In response to the apparent decline of amphibians at the end of the 20th century, the US Geological Survey established the Amphibian Research and Monitoring Initiative (ARMI) in 2000 to begin comprehensive studies to assess the status of amphibian species in the US (Corn et al. 2005). The overall research program was designed to provide resource managers with information necessary for amphibian conservation and to identify future research needs (e.g., Grant et al. 2013). Among a series of tasks, ARMI researchers were directed to establish a network of sites on US federal lands to monitor amphibian status and trends in the distribution and abundance of individual species and communities (Muths et al. 2005). Five 1US Geological Survey, Wetland and Aquatic Research Center, 7920 NW 71st Street, Gainesville, FL 32653. 2Current address - Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL 32611. *Corresponding author - terrapene600@ gmail.com. Manuscript Editor: Max Nickerson Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 530 National Wildlife Refuges (NWRs) on the Southeastern Coastal Plain were selected for potential monitoring, including St. Marks and Lower Suwannee in Florida, Harris Neck and Okefenokee in Georgia, and Savannah in South Carolina and Georgia. Other reports present the initial results from St. Marks (Dodd et al. 2007), Okefenokee (Smith et al. 2006b), Harris Neck (Dodd and Barichivich, 2007), and Lower Suwannee (Dodd et al. 2017) NWRs. Here, we present the results from our preliminary survey of the amphibians of Savannah NWR, the first such amphibian survey on the refuge. Field-site Description Savannah National Wildlife Refuge (SNWR) (Fig. 1) comprises 13,387 ha in Georgia (Chatham County) and South Carolina (Jasper County) immediately upstream along the Savannah River from the city of Savannah, GA. It is part of the Savannah Coastal Refuges Complex under the jurisdiction of the US Fish and Wildlife Service’s (USFWS) National Wildlife Refuge system. The refuge has an Figure1. Map showing the extent of Savannah National Wildlife Refuge and the location of sampling sites from 2004 to 2006. BI = Bear Island, DT = Dodge Tram Road, ND = North (Wildlife) Drive, ST = Solomon Tract, and WD = Wildlife Drive. Southeastern Naturalist 531 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 extensive history of human occupation and use, from Native Americans through the plantation era, when the bottomlands and freshwater tidal marshes were extensively diked and modified for rice production. Dike construction began in the mid-to-late 1700s, with peak rice harvests occurring from 1850 to 1860 (Rowland 1987, USFWS 2011). Established in April 1927, the refuge is primarily managed for waterfowl, and water levels within the former rice fields (1364 ha) are carefully regulated via 22 water-control structures. The refuge staff occasionally clears vegetation from impounded areas, resulting in a variety of marsh habitats of different depths, vegetation structure, and species composition. Specific management objectives seek to provide a refuge and breeding ground for native birds and other wildlife, protection for endangered and threatened species, a sanctuary for migratory birds, native habitat maintenance, and educational/recreational activities (USFWS 2011). The northern part of the refuge (upstream from the impounded freshwater tidal marshes) consists mostly of extensive tracts of bottomland hardwoods (2975 ha) and cypress–gum swamp (4726 ha) that may or may not be periodically flooded (Garman and Nielsen 1992). The habitat classification here and below is as depicted on Fig. 16 in USFWS (2011). In addition, there are forested islands within the main Savannah River channel. These islands, the largest of which is Bear Island (312 ha), contain small channels and an extensive number of woodland pools and “creeks” that hold water for varying amounts of time. There is only 1 large pond on the refuge (Kingfisher Pond, an old borrow pit; site DT-2 on Fig. 1) not associated with the bottomland forest. River bluffs and upland terraces on the refuge are few because the refuge boundary often terminates at the base of the river bluff. However, some upland hardwoods and forested slopes are present along Dodge Tram Road (sites DT in Fig. 1) on the north side of the river, and more extensive uplands, including bottomland forest and a very small area of oak hammock, are found on the south side of the river east of O’Leary (as marked on the USGS 7.5’ Port Wentworth topographical map). This 403-ha parcel, the Solomon Tract (sites ST on Fig. 1), was one of the most recent additions to SNWR when we began our study. We sampled this area in connection with the USFWS malformed frog survey (Reeves et al. 2013). Additional information on the climate and vegetative communities of SNWR is provided in USFWS (2011). Methods We used a variety of methods to sample amphibians at SNWR (Appendix 1) from 2004 to 2006. Terrestrial sampling techniques focused on diurnal time-constrained field searches (i.e., visual encounter surveys [VES]) in the open and under cover-objects (e.g., logs, rocks, leaf litter). We conducted terrestrial surveys along Dodge Tram Road in bottomland wetland forest and in upland hardwoods on the slopes, as well as in the Solomon Tract. Most terrestrial VES lasted 20–30 min per site, and were conducted by 2–4 observers. Aquatic sampling employed dip nets (Memphis Net and Twine Co., HDD-2 with 4.7 mm [3/16”] sq. Delta mesh), crayfish traps (Johnson and Barichivich 2004), aural surveys (incidental observations Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 532 while conducting VES and nocturnal road cruising), and visual-encounter observations. Typically, we deployed 2–4 crayfish traps per site per night depending on water availability. Aquatic sampling focused on the impounded wetlands and adjacent freshwater marshes, at Kingfisher Pond, and in the few small, shallow temporary pools located in the Solomon Tract. We sampled 28 sites in 2004 (25 wetlands, 3 terrestrial) in April, June/July, and October; we deployed crayfish traps for 60 trap nights. Terrestrial sampling focused on upland areas on Bear Island (along a 470-m survey transect previously established by the USFWS), the Solomon Tract, and along Dodge Tram Road. In 2005, we sampled 10 sites (4 wetland, 6 terrestrial) in March, 15 sites in May (11 wetlands, 4 terrestrial, including several additional sites on Bear Island), and 9 sites in July (5 wetland, 4 terrestrial). We only sampled 10 wetland sites in 2006. In addition to sampling, we examined Jasper and Chatham county museum records from the American Museum of Natural History (New York, NY), Carnegie Museum (Pittsburgh, PA), Charleston Museum (Charleston, SC), Florida Museum of Natural History (Gainesville, FL), Francis Marion University (Jeffrey Camper; Florence, SC), Georgia Museum of Natural History (Athens, GA), Georgia Southern University (Statesboro, GA), HerpMapper (https://www.herpmapper.org/), iNaturalist (https://www.inaturalist.org/), Museum of Zoology (University of Michigan; Ann Arbor, MI), North Carolina State Museum (Raleigh, NC), Savannah Science Museum (Williamson and Moulis 1994), and US National Museum (Washington, DC). No amphibians originating from SNWR were found in any of these holdings. The South Carolina Herpetological Atlas contains 2 amphibian records from SNWR (Hyla cinerea [Green Treefrog], Lithobates grylio [Pig Frog]) with several additional species found in close proximity (Ambystoma opacum [Marbled Salamander], Eurycea cirrigera Green [Southern Two-lined Salamander], Anaxyrus terrestris [Southern Toad], Hyla chrysoscelis [Cope’s Gray Treefrog], H. femoralis [Pine Woods Treefrog], H. squirella [Squirrel Treefrog], Lithobates catesbeianus [American Bullfrog]) southwest of Hardeeville along Purrysbur g Road. We collected standard abiotic field parameters likely to influence amphibian species distribution at most of the wetlands sampled. Using a Hydrolab® Quanta® water-quality meter, we measured water temperature (ºC), conductivity (μS/cm), pH, dissolved oxygen (mg/l), and % dissolved oxygen. Results From 2004 to 2006, we detected 22 species of amphibians (15 frogs, 7 salamanders) at SNWR, with a possible 23rd species (Siren intermedia [Lesser Siren]) unconfirmed (Appendix 1). The suspected Lesser Siren consisted of 3 individuals regurgitated by a Nerodia fasciata L. (Banded Watersnake) that we trapped in a crayfish trap on 26 May 2006. The state of digestion made identification impossible because identification as subadult S. lacertina (Greater Siren) could not be ruled out. We heard 2 additional species, Pseudacris ocularis Bosc and Daudin [Little Grass Frog]) and P. nigrita Le Conte (Southern Chorus Frog), calling on 24 March 2005 immediately adjacent to SNWR along Chisolm Road Southeastern Naturalist 533 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 (32°13.398'N, 81°5.647'W), which connects Dodge Tram Road with Purrysburg Road north–northeast of the refuge. The most amphibian species-rich wetland was Kingfisher Pond (n = 12; site DT-2), where we also observed huge numbers of Lithobates heckscheri (River Frog) tadpoles in late July 2005 (662 tadpoles in 4 traps on 28 July; 470 the next day). Tadpoles of this species form large schools, and we observed very large numbers of tadpoles gulping air even as we set and picked up crayfish traps. Although we found few species in the rice fields, these fields provide extensive habitat (1364 ha) for ranid frogs and aquatic salamanders (Amphiuma, Siren); these are the only areas where we found Greater Sirens and Amphiuma means (Two-toed Amphiuma). We detected no amphibians at site ND-5, an area along the Little Black River subject to extreme tidal fluctuation (2.7–4.5 m). We set traps at site WD-8 for 7 d in May and July 2005, but observed only a single Lithobates sp. at this open-marsh site; however, we trapped Twotoed Amphiumas and Pig Frogs at nearby site WD-5. We collected water-quality field parameters at 13 locations from 2004 to 2006, with multiple ponds sampled more than once or twice (Table 1). Water temperatures were generally warm (15.3–26.4 ºC) because we made all observations between March and October. The lowest conductivities, ≤100 μS/cm, were measured at sites located outside the river floodplain (DT-2, ST-2, ST-3, ST-5). Although these wetlands range in size and origin from tiny woodland pools to a 6-ha borrow pit, they appear to share a rainwater-dominated hydrologic regime. The remaining sites are in the flooplain and exhibited greater conductivities than those in uplands. With the exception of WD-5, these sites are within an agricultural area—historically rice fields—defined by a series levees and canals. While geographically nearby, WD-5 is located in a natural floodplain. The freshwater tidal influence of the Savannah River and its many tributaries may account for the general increase in conductivity; however, locations WD-3 and WD-8 were >1000 μS/cm. Sample locations tended to be neutral (pH 7.01) to slightly acidic (pH 6.10), with very little variation between sites and sampling events. Dissolved oxygen levels, both total and %, were low and variable across most sites. Although inadequate for most fish, 3 woodland pools, ST-2, ST-3, and ST-5, were among the most oxygen rich (>2 mgL-1 or 20%) of all the sites sampled. Discussion Publications suggest that 43 amphibians (17 salamanders and 26 frogs) might be found within the general vicinity of SNWR (Dorcas and Gibbons 2008, Jensen et al. 2008, Mitchell and Gibbons 2010). Because of specific habitat requirements and a dearth of uplands on the refuge, we would not expect many of these species to occur on site (e.g., temporary pond breeders such as, Ambystoma cingulatum Cope [Frosted Flatwoods Salamander], A. mabeei Bishop [Mabee’s Salamander], A. tigrinum Green [Eastern Tiger Salamander], Hyla gratiosa LeConte [Barking Treefrog], Pseudacris ornata Holbrook [Ornate Chorus Frog], Lithobates capito LeConte [Gopher Frog]), nor should some species, if present, be expected to occur widely within its boundaries (e.g., Hyla avivoca Viosca [Bird-voiced Treefrog]). Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 534 Table 1. Water-quality data collected during amphibian sampling at Savannah National Wildlife Refuge from 2004 to 2006, supplemented by data collected by the USGS National Water Quality Laboratory from 2006 to 2008. Means followed by standard deviations in parentheses. SpC = specific conductivity, % DO = percent dissolved oxygen. Water SpC DO Site 07/01/04 10/21/04 03/24/05 05/20/05 07/28/05 05/25/06 08/16/06 temp (°C) (μS/cm) (mg/L) pH % DO DT-2 X X X X X X X 23.4 (3.8) 37 (12) 1.38 (1.57) 6.10 (0.78) 14.9 (15.9) HQ-1 X X X X X 25.2 (2.5) 513 (212) 0.81 (0.48) 6.32 (0.36) 10.0 (6.2) ND-3 X X X X 26.4 (1.8) 279 (112) 0.88 (0.46) 6.48 (0.36) 10.7 (5.5) ND-4 X X X X 24.5 (1.2) 477 (170) 0.89 (0.62) 6.25 (0.36) 10.6 (7.2) ST-2 X X 23.5 (3.9) 66 (13) 3.21 (0.13) 6.90 (0.01) 35.5 (3.5) ST-3 X X 21.2 (1.4) 100 (8) 2.80 (1.13) 6.57 (0.55) 31.7 (13.4) ST-5 X 20.8 88 2.02 6.22 22.8 WD-3 X X X X X X 23.3 (3.7) 1009 (141) 1.37 (1.11) 6.63 (0.38) 14.6 (11.0) WD-4 X 20.0 554 0.97 6.70 10.7 WD-5 X 19.3 135 0.66 6.00 7.1 WD-6 X 15.3 853 2.27 7.01 22.8 WD-7 X X 22.6 (3.7) 855 (150) 1.51 (1.07) 6.64 (0.39) 16.5 (11.1) WD-8 X X 25.4 (2.4) 1915 (85) 0.33 (0.01) 6.28 (0.06) 4.1 (0.3) Southeastern Naturalist 535 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 We observed the Little Grass Frog and Southern Chorus Frog within sight of the refuge boundary in temporary upland pools. Several species (e.g., Southern Twolined Salamander, Pseudotriton montanus Baird [Mud Salamander], Stereochilus marginatus Hallowell [Many-lined Salamander]) may yet be found on the refuge. Still, the refuge contains substantial amphibian diversity, particularly those species that occupy the extensive marshlands bordering the lower Savannah River. The bottomlands, cypress–gum swamps, ravine slopes, and islands within the floodplain offer a diverse suite of habitats where species from the Piedmont uplands may enter into the lower Coastal Plain. Most of the amphibians we detected during our surveys are common in the lower Coastal Plain of South Carolina and Georgia (Dorcas and Gibbons 2008, Jensen et al. 2008, Mitchell and Gibbons 2010). Of particular interest, however, is the presence of Ambystoma opacum (Marbled Salamander) on Bear Island and possibly other islands within the Savannah River. This small (10 cm total length) terrestrial species deposits eggs under debris during the autumn in shallow depressions (Mitchell and Gibbons 2010). During winter rains, the shallow depressions fill and form pools in which the larvae hatch and complete development. This species is not known to cross open water, particularly large fast-flowing rivers, and may have colonized the river islands during floods. Alternatively, the species could have been present in backwater forests (Zone IV of Larson et al. 1981) and became subsequently isolated as the river changed course through the b road floodplain. Another unusual inhabitant of this region, both on the river islands and at Kingfisher Pond, is Anaxyrus fowleri (Hinckley) (Fowler’s Toad). This species is normally associated with the upland Piedmont Region, and is rarely found in the Coastal Plain along rivers downstream (Dodd 2013, Floyd 2008). The toad’s entry into the Coastal Plain was either facilitated by the riparian corridor, or toads could have been washed downstream from the Piedmont during floods. We did not detect Acris crepitans Baird (Eastern Cricket Frog), another species thought to enter the Coastal Plain through riparian corridors (Dodd 2013). The Bird-voiced Treefrog, enters SNWR only at the northern boundary of the refuge, where it was heard at the abandoned Chisholm Landing. Other species (Desmognathus cf. auriculatus [Southern Dusky Salamander], Notophthalmus viridescens [Eastern Newt], Plethodon variolatus [South Carolina Slimy Salamander], Gastrophryne carolinensis Holbrook [Eastern Narrow-mouthed Frog], Pine Woods Treefrog, River Frog) are not widely distributed throughout the refuge because of limited available habitat. These species appear to be common where found, however, and all are widely distributed outside the refuge boundaries, with the exception of Southern Dusky Salamander (Graham et al. 2010, Maerz et al. 2015). Mention should be made concerning the Desmognathus (dusky salamanders) found within SNWR. We observed dusky salamanders in the bottomland forest among the seeps and swampy areas west of Dodge Tram Road in South Carolina (Zones IV and V of Larson et al. 1981) and in the upland forest of the Solomon Tract on the Georgia side of the Savannah River. The systematics of Desmognathus Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 536 in the Coastal Plain, especially along the major rivers, is by no means clear. Coastal Desmognathus may be partitioned into a variety of clades that do not appear to follow clear biogeographic patterns (Beamer and Lamb 2008). In the lower portions of the Plain in South Carolina and Georgia, Desmognathus can be partitioned into numerous lineages, some more closely related to distant species (D. conanti Rossman [Spotted Dusky Salamander], D. fuscus Rafinesque [Northern Dusky Salamander], D. monticola Dunn [Seal Salamander]) than to nearby conspecifics. It may be that there are numerous morphologically cryptic species in this region (Beamer and Lamb 2008, Means et al. 2017), perhaps partitioned by habitat preferences. For the interim, we classify SNWR dusky salamanders as D. cf. auriculatus [Southern Dusky Salamander] until relationships are resolved. As noted by Yu et al. (2015), water-quality information reflects watershed environments and is valuable for assessing the suitability of wetlands for amphibians. Our preliminary water-quality indicators were typical of what might be expected for this region. Wetlands were generally slightly acid to neutral in pH, reflecting the tannic acid nature of the bottomland forest and the highly organic impounded wetlands. Many amphibians can tolerate rather acidic environments (references in Dodd 2013), and the pH readings we observed were well within the tolerance limits of these species-based laboratory observations (Freda 1986). With few exceptions, oxygen saturation tended to be low, again reflecting the highly eutrophic nature of the impounded wetlands exposed to intensive solar radiation, or to the small size of the nearly stagnant woodland pools. However, these values are also well within the range for field studies of anurans elsewhere (e.g., Dodd and Barichivich 2007, Noland and Ultsch 1981, Wassersug and Seibert 1976). Frogs frequently are found in waters with low DO, leading tadpoles to gulp air, especially during the latter stages of development when water temperatures are high in summer (Wassersug and Seibert 1976). This behavior likely facilitates long larval periods, particularly of ranids, in SNWR’s open canopied impounded wetlands and marshes. SNWR has not been the object of intensive land use after the bo ttomland forest was cleared for rice plantations in the 1700s and 1800s. Taxodium distichum (L.) Rich (BaldCypress) and other forest species were harvested throughout the riparian corridor, but today, this region is covered by dense 2nd- and 3rd-growth forest that is managed for hunting and other recreational use. Timber harvest is currently absent from the refuge, although pine plantations occur to the east of Dodge Tram Road. Urban development occurs along the western edge of the Solomon Tract right up to the border of the refuge. The lower impounded marshlands are managed for waterfowl, with occasional dredging that may adversely affect amphibians (Aresco and Gunzburger 2004). Access to many areas of the refuge is strictly regulated, with most human use occurring along a dirt road that allows visitors to view wildlife through the marshes, fishing along the river and at Kingfisher Pond, and seasonal hunting in some areas. These activities appear consistent with the maintenance of the amphibian community, despite occasional disruption from dredging. In general, protected areas contain only a fraction of amphibian biodiversity (Nori et al. 2015). However, it appears that many protected areas on the Southeastern Naturalist 537 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 Southeastern Coastal Plain contain a substantial number of amphibians (Table 2), except for some of the rarer species such as the 2 species of flatwoods salamanders and Southern Dusky Salamander. Plans to enlarge the refuge, as detailed in USFWS (2011), would add upland habitats that might contain additional species and expand the limited distribution of upland amphibians currently present. Expansion would also allow for the protection of core habitat for wetland-breeding amphibians (Semlitsch 2000, Semlitsch and Jensen 2001). Monitoring the SNWR amphibian community would enable biologists to assess the potential impacts of future environmental changes (e.g., sea-level rise, pollution, climate change, urban and silviculture encroachment; USFWS 2011) and management practices (e.g., prescribed fire, herbicide spraying, fluctuating water levels) (Lindenmayer and Likens 2010). Acknowledgments We thank the staff of SNWR for supporting and permitting our work at the refuge. ARMI research and monitoring activities at SNWR were conducted under USFWS Special Use Permits No. 41620-04016 and 05-41650-4. We thank Steve Bennett, Linda Casey, Julia Earl, Denise Gregoire, Joe Mitchell, and Clint Smith for assisting in some of the field surveys. We are grateful to Kevin Smith and Anna Tutterow for supplying South Carolina Table 2. Amphibian species richness on selected protected private, federal, and state lands on the Atlantic Coastal Plain of the Southeastern US (exclusive of peninsular Florida). NF = national forest, NP = national park, NS = national seashore, NWR = national wildlife refuge, SF = state forest, and WMA = wildlife management area. Location Area(ha) Salamanders Frogs Source Alligator River NWR 69,091 2 15 Meyers and Pike (2006) Altamaha River corridorA 58,208 18 23 Stevenson and Chandler (2017) Big Bend WMA 29,111 10 19 Enge and Wood (1998), Surdick (2013) Blackwater SFB - 6 10 Enge (2002) Congaree NP 10,633 6 21 Tuberville et al. (2005) Cumberland Island NS 36,415 5 12 Shoop and Ruckdeschel (2000) Francis Beidler Forest 1398 8 16 Hall (1994) Francis Marion NF 101,000 8 17 Schurbon and Fauth (2003) Great Dismal SwampC 57,469 8 19 Delzell (1979) Harris Neck NWR 1285 1 12 Dodd and Barichivich (2007) Ichauway Plantation 11,300 13 8 Smith et al. (2006a) Jug Bay Wetlands Sanctuary 200 7 12 Smithberger and Swarth (1993) Okefenokee NWR 182,727 16 21 Smith et al. (2006b) Roanoke River corridorD 8500 7 12 Lamb et al. (1998) Savannah NWR 13,387 7 15 This paper Savannah River Site 198,344 17 26 Gibbons and Semlitsch (1991) St. Marks NWR 27,500 13 21 Dodd et al. (2007), ongoing USGS surveys ASurveys of 2 private preserves and 11 Georgia Wildlife Management Areas. BSurveys of 2 small seepage bogs; area not given. CGreat Dismal Swamp NWR and Dismal Swamp State Park. DA series of 5 preserves jointly managed by The Nature Conservancy and Georgia-Pacific. Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 538 Heritage Program database records from Jasper County. Russ Webb and John Robinette of SNWR facilitated work on the refuge, and we greatly appreciate their assistance. Research was carried out under US Geological Survey animal care and use protocols for sampling and handling amphibians. This study was funded by the USGS Amphibian Research and Monitoring Initiative (ARMI). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government. This is contribution number 603 of the US Geological Survey’s Amphibian Research and Monitoring Initiative. Additional water-quality data are available from the National Water Information System (water data.usgs.gov/nwis) and the biological and water-quality data used herein can be found at doi.org/10.5066/F7ST7NRD. Literature Cited Aresco, M.J., and M.S. Gunzburger. 2004. Effects of large-scale sediment removal on herpetofauna in Florida wetlands. Journal of Herpetology 38:275–279. Beamer, D.A., and T. Lamb. 2008. Dusky salamanders (Desmognathus, Plethodontidae) from the Coastal Plain: Multiple independent lineages and their bearing on the molecular phylogeny of the genus. Molecular Phylogenetics and Evolution 4 7:143–153. Capps, K.A., K.A. Berven, and S.D. Tiegs. 2014. Modelling nutrient transport and transformation by pool-breeding amphibians in forested landscapes using a 21-year dataset. Freshwater Biology 60:500–511. Corn, P.S., E. Muths, M.J. Adams, and C.K. Dodd Jr. 2005. The US Geological Survey’s Amphibian Research and Monitoring Initiative. Alytes 22:65–71. Delzell, D.E. 1979. A provisional checklist of amphibians and reptiles in the Dismal Swamp area, with comments on their range of distribution. Pp. 244–260, In P.W. Kirk Jr. (Ed.). The Great Dismal Swamp. University Press of Virginia, Charlottesville, VA. 427 pp. Dodd, C.K., Jr. 1997. Imperiled amphibians: A historical perspective. Pp. 165–200, In G.W. Benz and D.E. Collins (Eds.). Aquatic Fauna in Peril: The Southeastern Perspective. Special Publication No. 1. Southeast Aquatic Research Institute, Lenz Design and Communications, Decatur, GA. 553 pp. Dodd, C.K., Jr. 2013. Frogs of the United States and Canada. Johns Hopkins University Press. 2 Volumes, Baltimore, MD. 962 pp. Dodd, C.K., Jr., and W. J. Barichivich. 2007. Establishing a baseline and faunal history in amphibian monitoring programs: The amphibians of Harris Neck, Georgia, USA. Southeastern Naturalist 6:125–134. Dodd, C.K., Jr., W.J. Barichivich, S.A. Johnson, and J.S. Staiger. 2007. Changes in a Florida panhandle Gulf Coast herpetofaunal community over a 28-year period. American Midland Naturalist 158:29–48. Dodd, C.K., Jr., W.J. Barichivich, S.A. Johnson, M. Gunzburger Aresco, and J.S. Staiger. 2017. Establishing a baseline: The amphibians of Lower Suwannee National Wildlife Refuge, Dixie and Levy counties, Florida. Florida Scientist 80:133–144. Dorcas, M., and W. Gibbons. 2008. Frogs and Toads of the Southeast. University of Georgia Press, Athens, GA. 238 pp. Duellman, W.E., and S.S. Sweet. 1999. Distribution patterns of amphibians in the Nearctic Region. Pp. 31–109, In W.E. Duellman (Ed.), Patterns of Distribution of Amphibians. Johns Hopkins University Press, Baltimore, MD. 648 pp. Earl, J.E., T.M. Luhring, B.K. Williams, and R.D. Semlitsch. 2011. Biomass export of salamanders and anurans from ponds is affected differentially by changes in canopy cover. Freshwater Biology 56:2473–2482. Southeastern Naturalist 539 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 Enge, K.M. 2002. Herpetofaunal drift-fence survey of 2 seepage bogs in Okaloosa County, Florida. Florida Scientist 65:67–82. Enge, K.M., and K.N. Wood. 1998. Herpetofaunal surveys of the Big Bend Wildlife Management Area, Taylor County, Florida. Florida Scientist 61:61–87. Floyd, T.M. 2008. Fowler’s Toad (Bufo (Anaxyrus) fowleri). Pp. 39–41, In J.B. Jensen, C.D. Camp, W. Gibbons, and M.J. Elliott (Eds.). Amphibians and Reptiles of Georgia. University of Georgia Press, Athens, GA. 575 pp. Freda, J. 1986. The influence of acidic pond water on amphibians: A review. Water, Air, and Soil Pollution 30:439–450. Garman, G.C., and L.A. Nielsen. 1992. Medium-sized rivers of the Atlantic Coastal Plain. Pp. 315–349, In C.T. Hackney, S.M. Adams and W.H. Martin (Eds.). Biodiversity of the Southeastern United States: Aquatic Communities. John Wiley and Sons, New York, NY. 779 pp. Gibbons, J.W., and R.D. Semlitsch. 1991. Guide to the Reptiles and Amphibians of the Savannah River Site. University of Georgia Press, Athens, GA. 131 pp. Graham, S.P., E.K. Timpe, and L.R. Laurencio. 2010. Status and possible decline of the Southern Dusky Salamander (Desmognathus auriculatus) in Georgia and Alabama, USA. Herpetological Conservation and Biology 5:360–373. Grant, E.H.C., E.F. Zipkin, J.D. Nichols, and J.P. Campbell. 2013. A strategy for monitoring and managing declines in an amphibian community. Conservation Biology 27:1245–1253. Hall, R.J. 1994. Herpetofaunal diversity of the Four Holes Swamp, South Carolina. US Department of Interior National Biological Survey, Resource Publication 198. Washington, DC. 43 pp. Hocking, D.J., and K.J. Babbitt. 2014. Amphibian contributions to ecosystem services. Herpetological Conservation and Biology 9:1–17. Jensen, J.B., C.D. Camp, W. Gibbons, and M.J. Elliott (Eds.). 2008. Amphibians and Reptiles of Georgia. University of Georgia Press, Athens, GA. 575 pp. Johnson, S.A., and W.J. Barichivich. 2004. A simple technique for trapping Siren lacertina, Amphiuma means, and other aquatic vertebrates. Journal of Freshwater Ecology 19:263–269. Lamb, T., R.W. Gaul Jr., M.L. Tripp, J.M. Horton, and B.W. Grant. 1998. A herpetofaunal inventory of the lower Roanoke River floodplain. Journal of the Elisha Mitchell Scientific Society 114:43–55. Larson, J.S., M.S. Bedinger, C.F. Bryan, S. Brown, R.T. Huffman, E.L. Miller, D.G. Rhodes, and B.A. Touchet. 1981. Transition from wetlands to uplands in southeastern bottomland hardwood forests. Pp. 225–273, In J.R. Clark and J. Benforado (Eds.). Wetlands of Bottomland Hardwood Forests, Volume 11. Elsevier, Amsterdam, The Netherlands. 401 pp. Lindenmayer, D.B., and G.E. Likens. 2010. The science and application of ecological monitoring. Biological Conservation 143:1317–1328. Maerz J.C., R.K. Barrett, K.K. Cecala, and J.L. Devore. 2015. Detecting enigmatic declines of a once common salamander in the Coastal Plain of Georgia. Southeastern Naturalist 14:771–784. Means, D.B., J.Y. Lamb, and J. Bernardo. 2017. A new species of dusky salamander (Amphibia: Plethodontidae: Desmognathus) from the eastern Gulf Coastal Plain of the United States and a redescription of D. auriculatus. Zootaxa 4263:467–506. Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 540 Meyers, J.M., and D.A. Pike. 2006. Herpetofaunal diversity of Alligator River National Wildlife Refuge, North Carolina. Southeastern Naturalist 5:235–252. Mitchell, J., and W. Gibbons. 2010. Salamanders of the Southeast. University of Georgia Press, Athens, GA. 324 pp. Muths, E., R.E. Jung, L. Bailey, M.J. Adams, P.S. Corn, C.K. Dodd, Jr., G. Fellers, W.J. Sadinski, C. Schwalbe, S. Walls, R.N. Fisher, A.L. Gallant, W.A. Battaglin, and D.E. Green. 2005. The US Department of Interior’s Amphibian Research and Monitoring Initiative (ARMI): A successful start to a national program. Applied Herpetology 2:355–371. Noland, R., and G.R. Ultsch. 1981. The roles of temperature and dissolved oxygen in microhabitat selection by the tadpoles of a frog (Rana pipiens) and a toad (Bufo terrestris). Copeia 1981:645–652. Nori, J., P. Lemes, N. Urbina-Cardona, D. Baldo, J. Lescano, and R. Loyola. 2015. Amphibian conservation, land-use changes, and protected areas: A global overview. Biological Conservation 191:367–374. Reeves, M.K., K.A. Medley, A.E. Pinckney, M. Holyoak, P.T.J. Johnson, and M.J. Lannoo. 2013. Localized hotspots drive continental geography of abnormal amphibians on US Wildlife Refuges. PLoS One 8:e77467. Rowland, L.S. 1987. Alone on the river: The rise and fall of the Savannah River rice plantations of St. Peter’s Parish, South Carolina. The South Carolina Historical Magazine 88:121–150. Semlitsch, R.D. 2000. Principles for management of aquatic breeding amphibians. Journal of Wildlife Management 64:615–631. Semlitsch, R.D., and J.B. Jensen. 2001. Core habitat, not buffer zone. National Wetlands Newsletter 23:5–6. Schurbon, J.M., and J.E. Fauth. 2003. Effects of prescribed burning on amphibian diversity in a southeastern US national forest. Conservation Biology 17:1338–1349. Shoop, C.R., and C. Ruckdeschel. 2006. Amphibians and reptiles of Cumberland Island, Georgia. Occasional Publications of the Cumberland Island Museum No. 2, St. Marys, GA. Smith, L.L., D.A. Steen, J.M. Stober, M.C. Freeman, S.W. Golladay, L.M. Conner, and J. Cochrane. 2006a. The vertebrate fauna of Ichauway, Baker County, GA. Southeastern Naturalist 5:599–620. Smith, L.L., W.J. Barichivich, J.S. Staiger, K.G. Smith, and C.K. Dodd, Jr. 2006b. Detection probabilities and site-occupancy estimates for amphibians at Okefenokee National Wildlife Refuge. American Midland Naturalist 155:149–161. Smithberger, S.I., and C.W. Swarth. 1993. Reptiles and amphibians of the Jug Bay Wetlands Sanctuary. The Maryland Naturalist 37(3–4):28–46. Stevenson, D.J., and H.C. Chandler. 2017. The herpetofauna of conservation lands along the Altamaha River, Georgia. Southeastern Naturalist 16:261–282. Surdick, J.A. 2013. An amphibian and reptile drift-fence survey of Big Bend Wildlife Management area, Gulf Coast of Florida. Florida Scientist 76:436–452. Tuberville, T.D., J.D. Willson, M.E. Dorcas, and J.W. Gibbons. 2005. Herpetofaunal species richness of southeastern national parks. Southeastern Naturalis t 4:537–569. US Fish and Wildlife Service (USFWS). 2011. Savannah Coastal National Wildlife Refuges Complex: Comprehensive Conservation Plan. Southeast Region, Atlanta, GA. 357 pp. Available online at https://www.fws.gov/southeast/planning/PDFdocuments/ Savannah%20FINAL%20CCP/Savannah%20Final%20CCP.pdf. Accessed 21 November 2017. Southeastern Naturalist 541 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 Wassersug, R.J., and E.A. Seibert. 1976. Behavioral responses of amphibian larvae to variation in dissolved oxygen. Copeia 1976:86–103. Williamson, G.K., and R.A. Moulis. 1994. Distribution of Amphibians and Reptiles in Georgia: Volume 2. Locality Data. Savannah Science Museum Special Publication No. 3. Savannah, GA. 712 pp. Yu, X., J. Hawley-Howard, A. L. Pitt, J.-J. Wang, R. F. Baldwin, and A.T. Chow. 2015. Water quality of small seasonal wetlands in the Piedmont ecoregion, South Carolina, USA. Effects of land use and hydrological connectivity. Water Research 73:98–108. Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 542 Appendix 1. Summary table of amphibians observed or collected during surveys at Savannah National Wildlife Refuge from 2004 to 2006. Habitats: (F) bottomland hardwood forest; (S) ravine slope between bottomland hardwood and upland forests consisting of mixed slope forest and low, swampy, springfed seeps; (P) large manmade permanent pond (Kingfisher Pond); (T) small woodland pool; (W) extensive freshwater marshes that were former rice fields; (U) upland deciduous forest. Sampling: (V) visual-encounter surveys, including litter searches, incidental captures, and detection of frog calls; (A) aquatic sampling using crayfish traps and dipnets. -An unidentified Lithobates was observed at WD-8. Site Bear Isl. BI-1 BI-4 BI-5 BI-6 BI-7 DT-1 DT-2 DT-3 DT-4 DT-5 DT-6 HQ-1 ND-1 ND-2 ND-3 ND-4 ND-5 Habitat F F F F F F S P S S S S W W W W W W Sampling V V V V V V V V V V V V A A A A A A Species Acris gryllus (Le Conte) X X X X X X (Southern Cricket Frog) Anaxyrus fowleri (Hinckley) X X (Fowler’s Toad) A. terrestris (Bonnaterre) X X X X X (SouthernToad) Gastrophryne carolinensis (Holbrook) X X X X (Eastern Narrow-mouthed Frog) Hyla avivoca Viosca X X (Bird-voiced Treefrog) Hyla chrysoscelis Cope X X X X X X X X X (Cope’s Gray Treefrog) H. cinerea (Schneider) X X X X (Green Treefrog) H. femoralis Bosc X X X X (Pine Woods Treefrog) H. squirella Bosc X X X (Squirrel Treefrog) Lithobates catesbeianus (Shaw) X X X (American Bullfrog) Southeastern Naturalist 543 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 Site Bear Isl. BI-1 BI-4 BI-5 BI-6 BI-7 DT-1 DT-2 DT-3 DT-4 DT-5 DT-6 HQ-1 ND-1 ND-2 ND-3 ND-4 ND-5 L. clamitans (Latreille) X X X X X X X X X (Green Frog) L. grylio (Stejneger) X X X X (Pig Frog) L. heckscheri (Wright) X (River Frog) L. sphenocephalus (Cope) X X X X X X X X X X X (Southern Leopard Frog) Pseudacris crucifer (Wied-Neuwied) X X X X (Spring Peeper) Amphiuma means Garden X X X (Two-toed Amphiuma) Ambystoma opacum (Gravenhorst) X X (Marbled Salamander) Desmognathus cf. auriculatus (Holbrook) X X X (Southern Dusky Salamander) Eurycea quadridigitata (Holbrook) X (Dwarf Salamander) Notophthalmus viridescens (Rafinesque) X (Eastern Newt) Plethodon variolatus (Gilliams) (South Carolina Slimy Salamander) Siren intermedia Barnes ? (Lesser Siren) S. lacertina Osterdam X X X X (Greater Siren) Species count 5 3 3 2 3 1 7 12 8 8 9 5 5? 2 4 5 4 0 Southeastern Naturalist C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 544 Site SCL1 ST-1 ST-2 ST-3 ST-4 ST-5 ST-6 WD-1 WD-2 WD-3 WD-4 WD-5 WD-6 WD-7 WD-8 # of sites Habitat W U T T T U U W W W W W W W W Sampling A A A A A A A A A A A A A A A Species Acris gryllus (Le Conte) X X X 10 (Southern Cricket Frog) Anaxyrus fowleri (Hinckley) 2 (Fowler’s Toad) A. terrestris (Bonnaterre) X X 7 (SouthernToad) Gastrophryne carolinensis (Holbrook) X 5 (Eastern Narrow-mouthed Frog) Hyla avivoca Viosca 2 (Bird-voiced Treefrog) Hyla chrysoscelis Cope X X X X X 14 (Cope’s Gray Treefrog) H. cinerea (Schneider) X X X X 8 (Green Treefrog) H. femoralis Bosc 4 (Pine Woods Treefrog) H. squirella Bosc X X 5 (Squirrel Treefrog) Lithobates catesbeianus (Shaw) X X 5 (American Bullfrog) L. clamitans (Latreille) X X X X 13 (Green Frog) L. grylio (Stejneger) X X X X X X 10 (Pig Frog) L. heckscheri (Wright) X 2 (River Frog) Southeastern Naturalist 545 C.K. Dodd, Jr. and W.J. Barichivich 2017 Vol. 16, No. 4 Site SCL1 ST-1 ST-2 ST-3 ST-4 ST-5 ST-6 WD-1 WD-2 WD-3 WD-4 WD-5 WD-6 WD-7 WD-8 # of sites L. sphenocephalus (Cope) X X X X X X X X X 20 (Southern Leopard Frog) Pseudacris crucifer (Wied-Neuwied) X 5 (Spring Peeper) Amphiuma means Garden X 4 (Two-toed Amphiuma) Ambystoma opacum (Gravenhorst) X 3 (Marbled Salamander) Desmognathus cf. auriculatus (Holbrook) X 4 (Southern Dusky Salamander) Eurycea quadridigitata (Holbrook) X X 3 (Dwarf Salamander) Notophthalmus viridescens (Rafinesque) X X X X X 6 (Eastern Newt) Plethodon variolatus (Gilliams) X X X X 4 (South Carolina Slimy Salamander) Siren intermedia Barnes 1? (Lesser Siren) S. lacertina Osterdam X X 6 (Greater Siren) Species count 1 4 3 8 8 2 9 3 2 8 2 2 1 3 0*