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The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been devastating amphibians globally. Two general scenarios have been proposed for the nature and spread of this pathogen: Bd is an epidemic, spreading as a wave and wiping out individuals, populations, and species in its path; and Bd is endemic, widespread throughout many geographic regions on every continent except Antarctica. To explore these hypotheses, we conducted a transcontinental transect of United States Department of Defense (DoD) installations along U.S. Highway 66 from California to central Illinois, and continuing eastward to the Atlantic Seaboard along U.S. Interstate 64 (in sum from Marine Corps Base Camp Pendleton in California to Naval Air Station Oceana in Virginia). We addressed the following questions: 1) Does Bd occur in amphibian populations on protected DoD environments? 2) Is there a temporal pattern to the presence of Bd? 3) Is there a spatial pattern to the presence of Bd? and 4) In these limited human-traffic areas, is Bd acting as an epidemic (i.e., with evidence of recent introduction and/or die-offs due to chytridiomycosis), or as an endemic (present without clinical signs of disease)? Bd was detected on 13 of the 15 bases sampled. Samples from 30 amphibian species were collected (10% of known United States' species); half (15) tested Bd positive. There was a strong temporal (seasonal) component; in total, 78.5% of all positive samples came in the first (spring/early-summer) sampling period. There was also a strong spatial component--the eleven temperate DoD installations had higher prevalences of Bd infection (20.8%) than the four arid (<60 mm annual precipitation) bases (8.5%). These data support the conclusion that Bd is now widespread, and promote the idea that Bd can today be considered endemic across much of North America, extending from coast-to-coast, with the exception of remote pockets of naïve populations.

The Upper Mississippi Embayment (UME) ecoregion covers approximately 141,895 km2 and historically supported 9,712,455 ha of bottomland deciduous forests, swamps, bayous, and rivers. Only about 500 ha (< 0.01%) of pre-settlement bottomland hardwood forest habitat in the Mississippi Alluvial Valley (MAV) in the UME remained by the 1940s because the timber was clearcut and the wetlands drained for agriculture. By 1983 only a few scattered cypress-tupelo swamps remained. We studied the freshwater turtle community in Allred Lake, Missouri, a rare remnant of this ecosystem and compared these results to those from two other study sites in the MAV, Big Oak Tree State Park (BOTSP), Missouri, and Coldwater River National Wildlife Refuge (CRNWR), Mississippi. Species richness included six species commonly found throughout the MAV. One species (Red-eared Slider, Trachemys scripta elegans) dominated density and biomass in all three assemblages. The occurrence of the six species we studied in man-made restored wetlands such as those in BOTSP and CRNWR indicate these turtles would adapt to restored wetlands in the MAV in southeastern Missouri and elsewhere in the ecosystem. We provide information on habitat features that could be included in restoration design and construction that would benefit turtles. Given the ongoing worldwide decline of turtles, consideration of turtle ecology and behavior in wetland restoration projects in the MAV may be warranted.

We conducted a survey of freshwater turtle populations in the spring-fed Ichetucknee River in northern Florida to assess temporal variation in assemblage structure. Following the same protocols as an initial 2007 survey, we hand-captured turtles while snorkeling in 2014 and found changes in species composition, abundance of 3 species, and demographic composition of 2 species. We observed a shift in the most frequently captured species from Sternotherus minor (Loggerhead Musk Turtle) in 2007 to Pseudemys concinna (River Cooter) in 2014. We attribute this shift to an increase in the abundance of adult River Cooters. Long-term studies are needed to evaluate whether the changes we observed represent trends and which environmental factors may be driving them.

Animals aggregate to reduce predation risk, facilitate mating, and access resources with patchy distributions. During a long-term study of turtle populations in the Santa Fe River (SFR) ecosystem in northern Florida, we observed a large aggregation of turtles at Gilchrist Blue Springs Park (GBSP) in August–October 2013 and again in March–May 2014. On 8 September 2013, we hand-captured 496 turtles of 5 species in GBSP. The Suwannee cooter (Pseudemys concinna suwanniensis) was the most abundant species in the sample, with 477 individuals representing all demographic groups. Density of this species was 530 turtles/ha and biomass was 2242 kg/ha. We hypothesize that hydrological changes in the SFR basin contributed to the temporary turtle aggregations at GBSP. The 113-km SFR originates as a tannin-stained blackwater stream, but receives input of clear water from ≥ 45 artesian springs in its lower 37 km. Heavy rainfall in the upper SFR basin from Tropical Storm Debby in June 2012 resulted in a large influx of tannic water that overwhelmed the capacity of the springs to dilute the river water. This storm in combination with additional episodes of heavy rainfall and declining spring flows led to an unusually long (34-mo) tannic period in the typically clear lower 37 km of the SFR. The resulting loss of most submerged aquatic macrophytes in the river due to insufficient sunlight may have been the stimulus that led the herbivorous P. c. suwanniensis to seek food in one of the few locations that had abundant submerged aquatic vegetation in 2013 and 2014. Turtles previously marked upriver (to 16 km) and downriver (to 4.6 km) from GBSP were in the aggregation, suggesting the individuals gathered at GBSP represented a large portion of the SFR P. c. suwanniensis population.

Macrochelys suwanniensis is a newly described species endemic to the Suwannee River drainage in the southeastern United States. We conducted a study of M. suwanniensis in the Santa Fe River (SFR), the major Florida tributary of the Suwannee River, between 2004 and 2011. We captured 109 individuals (24% immature, 44% adult female, 32% adult male). Adult males (mean straight midline carapace length [CL]  =  530.7 mm, mean mass  =  34.0 kg) were significantly larger than adult females (mean CL  =  424.0 mm, mean mass  =  17.2 kg), with a sexual size dimorphism index of −0.25 based on mean CL. The largest turtle in our study was 623 mm CL and weighed 54.4 kg. Adult females were significantly larger (CL) in the lower SFR than in the upper SFR (these reaches are separated where the river flows underground for 5 km). All adult males > 600 mm CL were captured in the lower SFR. Adult females were proportionately heavier in the upper SFR than in the lower SFR; males did not show this difference. We hypothesize that these differences in body size are related to habitat. The M. suwanniensis population in the SFR presently appears healthy, but we suggest this species requires continued protection because of vulnerability of adults to harvest.

Sirens are enigmatic, fully aquatic salamanders found in freshwater wetland habitats. Siren intermedia intermedia (Eastern Lesser Siren) occurs along the East Coast of the United States from Alabama to Virginia. Surveys near the northeastern range edge of the subspecies at Fort A.P. Hill in Virginia from 1995 to 1999 documented 53 Eastern Lesser Sirens in 5 wetlands. In 2015, 13 individuals were found, documenting persistence at 4 of these wetlands; none were found in 4 additional wetlands with habitat that appeared appropriate. The size distribution of captured individuals was similar for the 2 survey periods. Captured individuals in 2015 were screened for Batrachochytrium dendrobatidis (Bd), a fungal pathogen ubiquitous in aquatic habitats of the southeast and mid-Atlantic. No Bd was detected on these individuals, despite the presence of Bd on other amphibians at Fort A.P. Hill. Further investigations of the Eastern Lesser Siren populations in this area would provide important information about the persistence of this species in the region and provide more insight into the biology of this elusive salamander.

We scored 48 Malaclemys terrapin nests destroyed by raccoons on Fisherman Island, Virginia, for the presence or absence of tree canopy, shrub canopy, no canopy, bare sand, grass cover, and herbaceous cover. Significantly more nests than expected were found in the open with no vegetation cover and observed distances of predator-destroyed nests from the edge of the nearest habitat island of woody vegetation were significantly different from a normal distribution; most were placed near the island margin. Our results underscore the need to understand the influence of predator search behavior on terrapin nest survival in different habitat types.

Bog turtle (Clemmys muhlenbergii) populations are believed to be declining, in part, because of habitat loss. However, a detailed understanding of the specific habitat requirements for bog turtles is lacking. We used radiotelemetry on adult bog turtles to examine home range size (M: n = 13; F: n = 12) and habitat selection (M: n = 12; F: n = 17) at 3 sites in southwestern Virginia from May 1995 to December 1996. Home range size did not differ between males and females, as calculated via minimum convex polygon (MCP) analysis (P = 0.785) or cluster analysis (P = 0.722) during the 20-month study period. Habitat selection also did not differ by sex (P = 0.441). Mean 95% home range area pooled across sexes was 0.52 ha via MCP analysis and 0.15 ha via cluster analysis. We located bog turtles in areas closer to patches of shallow water, in deeper mud (21 cm) and water (9 cm), and in taller (55 cm), denser vegetation than expected if selection was random. Bog turtles selected wet meadow, smooth alder (Alnus serrulata) edge, and bulrush (Scirpus spp.) vegetation types more than expected randomly, and avoided dry meadow vegetation and streams. This species selects multiple microhabitats within wetlands and is restricted to small home ranges. Future bog turtle habitat conservation in southwestern Virginia should identify occupied wetlands containing the habitat components we describe, quantify management practices aimed at slowing succession and habitat loss, and reduce threats that may affect wetland hydrology.

Some people seem to be born leaders and Vic Hutchison is one of them. He has served in such a capacity in numerous and varied organizations throughout his life. Early on, he showed leadership in high school and the Boy Scouts. Even in late retirement he is the Manager of the Oklahoma Evolution List Serve where he alerts teachers around the state of pending anti-evolution and anti-science legislation in the state legislature. Vic's legacy is his leadership. Behind this commanding presence was always kindness, dedication, motivation, and support. After graduation, he was on active duty in the US Army for two years. During that time he graduated from officer infantry school at Fort Benning, Georgia, as a Second Lieutenant and subsequently trained infantry soldiers at Camp Atterbury IN. He later served in the Medical Service Corps until he was shipped to Korea. During his eight months in-country (November 1953-May 1954), he was Commander of the Ambulance Company in the Third Infantry Division.