Michael J. Pinder

Virginia Department of Game and Inland Fisheries

2206 South Main Street, Suite C

Blacksburg, Virginia 24060

Southeastern Virginia contains some of the highest numbers of reptile and amphibian species in the Commonwealth. A total of 19 anuran, 12 salamander, 23 snake, 12 turtle, and 8 lizard species are known from this portion of Virginia (Tobey, 1985; Mitchell, 1994). Climate, habitat, and geography contribute to this species diversity. The warm coastal waters provide this area with mild winters and hot, humid summers. Coastal dunes, blackwater rivers, and Lake Drummond, one of only two natural lakes in Virginia, offer a wide variety of habitats. Additionally, the Great Dismal Swamp, an expansive pocosin, contains vegetation such as bald cypress (Taxodium distichum), pond pine (Pinus serotina) and spanish moss (Tilandsia usneoides), which are more commonly found in southern clines. These factors allow many southern species to extend their northern distributions to southeast Virginia. The eastern glass lizard (Ophisaurus ventralis), chicken turtle (Deirochelys reticularia), lesser siren (Siren intermedia), and the southern toad (Bufo terrestris) are at their northern most distribution in this portion of the state.

The Naval Security Group Activity (NSGA) Northwest is a 961 ha radar station operated by the U.S. Navy located in the southeast corner of the City of Chesapeake, Virginia and into the northeast corner of North Carolina. This large section of property contains unique and rare species such as the two-toed amphiuma (Amphiuma means) and the state endangered canebrake rattlesnake (Crotalus horridus). Over the last two years, the U.S. Navy has funded Dr. Alan Savitsky of Old Dominion University to study the seasonal ecology of canebrake rattlesnakes. By implanting snakes with radio transmitters, researchers have been able to track the movements of canebrakes. Information gathered from this research will assist resource managers in the conservation of this species. The Virginia Department of Game and Inland Fisheries (VDGIF) has been recently contracted by the facility to conduct a reptile and amphibian survey. The study will continue until summer 1999. In addition to these projects, a new environmental center has been built at the facility to educate the public about the region's unique flora and fauna.

The Virginia Herpetological Society (VHS) annually selects one portion of the state to survey reptiles and amphibians. These sites are distributed throughout Virginia and are in need of additional sampling. Selection criteria requires that the site can be resurveyed at a later date in order to develop a species list of the area. The site selected for the 1997 survey was the NSGA Northwest property, City of Chesapeake, Virginia.

The NSGA Northwest is located in the Coastal Plain physiographic province and adjoins the eastern portion of the Great Dismal Swamp National Wildlife Refuge. The base is dominated by mixed forest types such as bald cypress, loblolly pine (Pinus taeda) and a variety of oak species (Quercus sp.). Landuse surrounding the base is primarily agricultural and forested. Habitat types include flooded woodlands, open fields, ditches, streams, and small ponds.

On May 10-11, 1997, the VHS membership conducted an intensive reptile and amphibian survey on the NSGA facility, City of Chesapeake, Virginia. The majority of sampling occurred between 1000 hrs and 1900 hrs. The base was sectioned into six sampling areas and a survey team was assigned to each section. Survey sites are presented in Figure 1. Minnow traps were placed to capture large aquatic amphibians, and chicken wire turtle traps, baited with sardines, were set to capture aquatic turtles. Most of the facility was sampled except for restricted areas and portions of the facility in North Carolina.

Each team was equipped with dip nets, thermometers, sample jars and containers. Specimens were positively identified and when possible, measured, weighted, sexed, and life stage (e.g., juvenile, adult, etc.) recorded. Frogs were identified either by examination or by vocalizations. Basking turtles were observed with the assistance of binoculars. Habitat and behavior was recorded for each observation. Below is an account of each species encountered and includes habitat, distribution, life stage, and site location:

Bufo spp. There are three toad species including hybrids that could be found in the survey area. They include B. americanus americanus Holbrook.

B. fowleri (Hinckley), and B. terrestris (Bonnaterre). Nineteen toads were collected under boards, forest litter, in road ruts, and low vegetation. Tadpoles were found in an ephemeral pools in an open field. Site locations: I, III, V, VI.

Grastrophryne carolinesis (Holbrook). One adult and one juvenile eastern narrowmouth toad were found under boards and debris. Site location: III.

Hyla chrysoscelis (Cope). An immature Cope's gray treefrog was found on a tree near standing water. Site location: IV.

Hyla squirella (Latreille). Two juvenile (both 25 mm ) and 4 adult squirrel treefrogs (includes one female w/eggs 35 mm SVL) were found hiding under brush and in a wood pile. All specimens were found in mixed oak-pine forests. Site locations: I, V.

Pseudacris ocularis (Bosc and Daudin). Seven adult little grass frogs were found in road ruts containing emergent vegetation. Site location: III.

Rana catesbeiana (Shaw). Three adult and one subadult bullfrogs were found basking along a ditch and pond edge. Tadpoles were observed in the shallow portion of Lunker Lake. Site locations: I, II, III, VI.

Rana clamitans (Rafinesque). Five adult and one subadult green frogs were found in road ruts, ditches, and near stream banks. One frog was missing a front leg, which may have been the result of turtle predation. Green frogs were observed basking and heard vocalizing. Site locations: II, III, V, VI.

Rana utricularia (Harlan). Seven adult and two subadult southern leopard frogs were found in a variety of habitats including grassy trails, water filled ruts containing vegetation, and small streams. Tadpoles were found in small, ephemeral pools in a field. Site locations: II, III, V, VI.

Ambystoma opacum (Gravenhorst). One juvenile specimen of marbled salamander was found under a rotten log. Site location: IV.

Plethodon chlorobryonis (Mittleman). Twelve Atlantic coast slimy salamanders were found under logs and moist woodlands. Snout-vent lengths of four individuals were 20 mm, 20 mm, 65 mm, and 66 mm. Site locations: I, III.

Plethodon cinereus (Green). Seventeen redback salamanders were found during our survey. Specimens were observed hiding under logs and plywood in forested areas. Both lead and red phases were present. Redback salamanders were the most abundant salamanders. Site locations: I, III, V.

Eumeces fasciatus (Linnaeus). Two adult five-lined skinks were found basking next to stumps in deciduous woodlands. One individual was a male measuring 70 mm SVL. Site location: I.

Eumeces inexpectatus (Taylor). Four adult southeastern five-lined skinks were found hiding under boards and rocks. One individual was found along a ditch. Site locations: II, III.

Eumeces laticeps (Schneider). Four adult broad-headed skinks were found basking and hiding in and on wood piles. Site location: V.

Scincella lateralis (Say). Seven adult ground skinks were under boards, debris, and in grassy areas near potted plants. Site locations: I, II, III, V.

Carphophis amoenus amoenus (Say). Two adult eastern worm snakes (one female 210 mm SVL) in our survey. One was found under debris and the other in a dump area. Site locations: III, V.

Coluber constrictor constrictor Linnaeus. One adult northern black racer was found basking along a dirt road bordering a deciduous swamp. Site location: I.

Diadophis punctatus punctatus (Linnaeus). Two adult southern ringneck snakes, one measuring 200 mm SVL, were found under asphalt shingles and rocks. Site location: I.

Elaphe obsoleta obsoleta (Say). Two adult black rat snakes were found during this survey. One was found along a pond edge, while another was observed preying on starling nestlings. Site location: II.

Heterodon platirhinos (Latreille). One juvenile eastern hognose snake measuring 230mm SVL was found in leaf litter of a mixed oak-pine forest. Observers indicated that the specimen regurgitated a freshly digested toad. Site location: I.

Lampropeltis getula getula (Linnaeus). Of the 3 eastern kingsnakes we found, one specimen was observed hiding under railroad ties, another in concrete blocks, and the other basking along a grassy path. One adult male measuring 900 mm SVL and semi-adult female measured 650 mm SVL. Site locations: III, VI.

Nerodia erythrogaster erythrogaster (Forster). Two red-bellied water snakes, one adult and one juvenile, were found in ditches. Specimens were observed swimming and basking. Site locations: I, IV.

Thamnophis sirtalis sirtalis (Linnaeus). One adult eastern garter snake was found basking along a grassy lake bank. Site location: II.

Thamnophis sauritus sauritus (Linnaeus). One juvenile eastern ribbon snake was found along a grassy trail near water. Site location: III.

Chelydra serpentina (Linnaeus). One common snapping turtle was found dead on a road that paralleled a ditch. Site location: VI.

Chrysemys picta picta (Schneider). Eight adult painted turtles were observed basking along a ditch. Three other adult turtles were seined from a ditch. One juvenile turtle was found dead along Lunker Lake. Site locations: II, IV, VI.

Clemmys guttata (Scheider). Two adult male and one adult female spotted turtles were in a flooded woodland and along a pond edge. Carapace lengths of male turtles were 100.8 mm and 100.1 mm. Site location: III.

Kinosternon subrubrum subrubrum (Bonnatere). Two adult eastern mud turtles, 45 mm and 72 mm, were collected in our survey. One specimen was caught in a trap and the other was found in a drainage ditch under a rotten log. Leeches were attached to one of the turtles. Site location: V, VI.

Sternotherus odoratus (Latreille). One juvenile and one adult stinkpot were found in mud and along a canal. The adult turtle measured 60.75 mm CL. Site locations: II, IV.

Terrepene carolina carolina (Linnaeus). One adult male eastern box turtle was found in the understory of a mixed oak-pine forest. Site location: V.

Trachemys scripta scripta.(Schoepff). Two adult yellow-bellied sliders were found basking in this survey. Habitats include a log near a pond and on the bank of a small stream. Site location: II.

A total of 10 anurans, 3 salamanders, 4 lizards, 9 snakes, and 7 turtles were collected in our survey. We collected less than 46% of the species recorded from the City of Chesapeake (Table 1). The discrepancy between number collected and known species may be partly explained by the unseasonably poor weather on the main survey day. On May 11, 1997, the weather was windy, overcast, and cold with temperatures as low as 17°C. In such conditions, many reptiles and amphibians that regularly bask would be difficult to find. Anurans were especially under represented in our survey. Of the 19 anuran species known from the base, we collected less than half and even common species such as the pickerel frog (Rana palustris) were not found. Regardless of weather conditions, certain species like the eastern spadefoot toad (Scaphiopus holbrookii holbrookii) would be unlikely in such a limited survey.

The ranges of several toad species are known to overlap in Southeast Virginia. B. terrestris is at its northern most distribution where it is known to hybridize with B. fowleri (Tobey 1985). Furthermore, there is possible three way hybridization with the two species listed above and B. americanus (Mitchell pers. comm). B. americanus is documented just south into North Carolina (Conant and Collins 1991). Because no vouchers were collected during our survey, proper species verification or determination of hybrids was not possible. To resolve this problem, electrophoretic and DNA analysis should be conducted on specimens from southeast Virginia and compared to specimens across the range of these species.

The protection of canebrakes at the NSGA Northwest facility is considered critical to reclassify this species from endangered to threatened (VDGIF 1993). Our survey failed to find any canebrake rattlesnakes even though they are well documented at the facility (Mitchell 1993). Rattlesnakes are known to occupy oak-pine forests, canefields, and swamps, which are habitats present on the survey area (Mitchell 1994). The inability of our survey to find this species demonstrates the snake's secretive and elusive nature. Canebrakes have light tan to brown background and dark brown to black chevron bands, characters that allow them to be well camouflaged on leaf litter in the forest floor (Mitchell 1994). They are also "sit and wait" predators and will remain motionless for hours, thereby remaining undetected by most observers. Further survey work will be required to determine the population level and habitat use of canebrake rattlesnakes in this area.

Only a few management recommendations can be provided for a short term survey. Many species of frogs and aquatic turtles were present in two small ponds Except for its upper end, the pond known as Lunker Lake had its grassy shoreline mowed down to the water's edge. Allowing some grass to grow uncut, even on the wetted margins of the shoreline, would be a great benefit to anurans and snakes. Additionally, placing a few logs gently angled in the water would provide excellent habitat for basking turtles (Johnson, 1994). Although no amphiumas or sirens were found, the ditches containing aquatic vegetation provides good habitat for these species (D. Schwab pers. comm.). Herbicides should not be used near or on these areas. The flooded woodlands are excellent habitat for spotted turtles. Like other members of the genus Clemmys, this species is vulnerable to habitat degradation and commercial collection. Ditching, road building, and other activities negatively affecting these wetlands should be avoided. Individuals should not be allowed to remove any native fauna without the mutual consent of facility and wildlife agency authorities. Dead standing trees, stumps, and logs all provide good shelter and feeding habitat for reptiles and amphibians and should not be removed. More recommendations will accompany the final VDGIF survey report (D. Schwab pers. comm.).

The City of Chesapeake is one of the fastest growing regions in Virginia. As roads, malls, and subdivisions encroach the countryside, natural areas are becoming smaller and fragmented. Species that once had free movement are confined to a few protected areas. Therefore, large tracts of land such as the NSGA Northwest facility will be critical in the future protection of many species. The first requirement in providing longterm protection will be to conduct species and habitat inventories In this regard, the VHS will continue to conduct these surveys to ensure the conservation of Virginia's reptiles and amphibians.

We are greatly appreciative to the following VHS members and guests for making this survey possible: Mitch Bolling, David Dawson, Chris d'Orgeix, Faye Ferrall, Whitney Ferrall, Shay Garriock, Bob Greenlee, Sara Greenlee, Mike Hayslett, Carol Heiser, Sara Heiser, Bill Henley, McKeever Henley, Jess Jones, Don Mackler, Tim Mathies, Konrad Mebert, Rob McGarvey, David Perry, Steve Perry, Dirk Rodgers, Gene Sattler, Paul Sattler, Don Schwab, Don Schwab Jr., Jim Scranton, Gina Shepard, and Laurie Zuckerman. Thanks to Don Schwab, VDGIF and Pam Couch, NSGA Northwest Facility for their assistance in obtaining permission and access, and Shay Garriock and Paul Sattler for editorial assistance. The omission or misspelling of any person(s) who helped in this survey is purely accidental.

Conant, R., and J.T. Collins. 1991. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. 3rd ed. Houghton Mufflin Co., Boston. 450 pp.

 

Johnson, T. 1994. Amphibian and reptile management on conservation department impoundments. Missouri Department of Conservation, Natural History Division. 14 pp.

Mitchell, J.C. 1993. Distribution and status of canbrake rattlesnake (Crotalus horridus) sites in southeastern Virginia. Virginia Department of Game and Inland Fisheries, Richmond. 148 pp.

Mitchell, J.C. 1994. Reptiles of Virginia. Smithsonian Institutional Press, Washington, D.C. 352 pp.

 

Tobey, F.J. 1985. Virginia's amphibians and reptiles, a distributional survey. Virginia Herpetological Society, Purcellville. 114 pp.

Virginia Department of Game and Inland Fisheries. 1993. Canebrake Rattlesnake Recovery Plan. Nongame and Endangered Wildlife Program. VDGIF, Richmond, VA. 22 pp.