Thomas K. Pauley

Life History of the Hellbender, Cryptobranchus alleganiensis, in a West Virginia Stream

Abstract Though locally abundant throughout the high mountains of West Virginia, intensive studies on the natural history and population structure of the hellbender, Cryptobranchus alleganiensis, have not been conducted in the state. From 1998–2000 we conducted a mark-recapture study within a 216 × 18 m stream section in east-central West Virginia using diurnal and nocturnal survey methods. Ninety-nine captures of 44 individuals were recorded. Density estimates ranged from 0.8–1.2 individuals/100 m2. The sex ratio was 1.2:1. Sexual dimorphism was apparent, as females were longer and heavier than males. However, the longest males were underweight compared to their predicted mass. This population was highly skewed toward large adults, and larvae and juveniles were not encountered. The mean inter-capture distance was 35.8 m and 95% MCP home range estimates averaged 198 m2. Water depth where hellbenders were captured ranged from 16–56 cm and individuals were never captured in heavily silted areas. Hellbender size was not correlated to rock size and not more than one individual was found beneath a single rock. We suggest that more thorough searches focusing on larval and juvenile habitat are needed before accurate assessments of population health can be made in this and other streams in West Virginia.

Resource Allocation and Life History Traits of Plethodon cinereus at Different Elevations

Abstract Ecologists have long studied extrinsic factors to explain intraspecific variation in phenotypic expression, yet assessment of intrinsic factors may also be important in understanding intraspecific phenotypic variation. Resources are allocated among the competing life history traits of growth, reproduction and storage. Thus, assessment of the suite of these traits may be critical to better understand phenotypic expression of life history traits. We examined growth (body size), reproduction (reproductive frequency) and storage (tail fat) of museum specimens of Red-backed Salamanders, Plethodon cinereus, at low and high elevations to test how altitudinal differences affected resource allocation among these life history traits. Based on the findings from previous studies, we hypothesized that animals at high elevations would be smaller in body size, reproduce less frequently and have less fat storage. We found that adult animals at high elevations were smaller in body size, reproduced less frequently (only females), but had greater tail fat storage relative to their body size than their counterparts at low elevations. The stored fat on tails can be used when salamanders are short of food. It may be more crucial for animals at high elevations to store more fuel for survival because longer and colder winters prevent them from actively foraging for longer periods. Our results suggest that resource allocation to growth and reproduction may be more constrained at high elevations because of the shorter growing season and greater allocation of energy into storage.

The Appalachian Inferno: Historical Causes for the Disjunct Distribution of Plethodon nettingi (Cheat Mountain Salamander)

Abstract The original Picea rubens (Red Spruce) forest in West Virginia covered approximately 1.5 million acres, most of which was eliminated between 1870 and 1920 by clear-cutting and conflagrations. The total range of Plethodon nettingi (Cheat Mountain Salamander) was confined within this Red Spruce forest. Fires burned the duff and soil to the bedrock in many places, thus eliminating salamander habitats. It is hypothesized that Cheat Mountain Salamanders were eradicated throughout much of their range, and only areas with large emergent rocks or boulder fields provided refugia where they survived.

Amphibian use of man-made pools on clear-cuts in the Allegheny Mountains of West Virginia, USA

Timber harvesting can alter habitats of forest-dwelling species and these alterations can be highly detrimental to species such as amphibians that are intimately associated with habitat temperature and moisture regimes. Consequently, information on conservation practices that can reduce impacts on these species can be useful to prevent local extinctions. Twenty-two of 40 pools constructed by the Fernow Experimental Station, USDA Northern Research Station, Parsons, West Virginia in 1993 on primitive haul roads in two clearcut areas on McGowan Mountain, Tucker County, WV were monitored for 3 years to determine their potential use by anurans. Monthly samples (April through September) of water chemistry and amphibian captures were taken to evaluate amphibian use of these pools. Anurans that used the pools to breed were Bufo americanus americanus, Rana sylvatica, Psuedacris brachyphona, and Hyla chrysoscelis. Desmognathus ochrophaeus and Gyrinophilus porphyriticus porphyriticus were also found in ponds but no evidence of breeding was discovered. By 1994, 14 of the 22 pools that held water were used by anurans for reproduction. Species richness of anurans that bred in pools was primarily dependent on pond depth. Man-made small but deep ponds placed carefully such that their hydroperiods are long enough for larvae to complete development (i.e., near seepages) provides breeding habitat for some frogs species, as well as refugia for non-breeding frogs and salamanders in clear-cut areas. Pools constructed at strategic locations on primitive roads have the potential to reduce adverse impacts of timber harvesting on some amphibian populations.

Green Salamander (Aneides aeneus) Growth and Age at Reproductive Maturity

Abstract Growth and age at reproductive maturity are two life-history parameters that add an important temporal component to species conservation, yet such information is seldom available for plethodontid salamanders. We modeled growth and age at maturity for a northern West Virginia population of Green Salamanders, Aneides aeneus, using snout–vent length (SVL) growth intervals from a five-year mark-recapture study. Growth data were fit to the von Bertalanffy and logistic growth interval models and compared using the residual error mean square. The logistic model provided the best fit to the recapture data, indicating that Green Salamanders grow slowly for plethodontids and that it takes 7–8 yr to reach reproductive maturity. Our results revealed that Green Salamanders mature at a later age than most plethodontid species, indicating that the species might have greater generation time and longevity than previously suspected. Our data may offer insight into why the species is sensitive to population declines. Thus, we suggest that future research focus on Green Salamander longevity and generation time to provide a framework from which comparisons can be made across populations.

Diets of Sympatric Black Mountain and Seal Salamanders

Abstract We studied the diet of Desmognathus welteri (Black Mountain Salamander) and compared it with the diet of D. monticola (Seal Salamander) in sympatry, using stomach contents. The diets of the two species were 86.6% similar, with four of five top prey categories in common. The most numerically important prey items for both species were adult dipterans and coleopterans and winged hymenopterans. Desmognathus welteri consumed a larger percentage of aquatic prey. No salamander remains were found in the stomachs of either species, weakening the supposition that large desmognathines are significant predators on small ones. We suggest that the differences in diet are a result of differences in micro-habitat use and body size.

Decline of the Cheat Mountain Salamander over a 32-Year Period and the Potential Influence of Competition from a Sympatric Species

Abstract We evaluated trends in occupancy of the Cheat Mountain Salamander (Plethodon nettingi) over a 32-yr period and examined the potential influence of competition by sympatric salamander species on these changes. We conducted surveys at 36 locations along four transects on an elevational gradient in the Appalachian Mountains geographic province of West Virginia, USA. We used occupancy modeling to examine patterns in species distributions for three focal species: P. nettingi, a federally threatened species, the Eastern Red-Backed Salamander (Plethodon cinereus), and the Allegheny Mountain Dusky Salamander (Desmognathus ochrophaeus). The probability of occupancy for P. nettingi was considerably lower in 2011 compared to 1978–79 at medium and high elevations (1,169–1,378 m). Additionally, occupancy of P. nettingi was associated negatively with P. cinereus at the highest elevations. These data suggest that these P. nettingi populations have declined and P. cinereus have possibly expanded their vertical distribution. Thus, P. cinereus may be negatively affecting mid- and high-elevation populations of P. nettingi. Alternatively, environmental changes (e.g., habitat disturbance and altered weather patterns) may have contributed to declines of P. nettingi at mid- and high-elevation sites, facilitated by colonization by P. cinereus. Due to the endemic and federally threatened status of P. nettingi, conservation efforts to avoid fragmentation of P. nettingi habitat should be maintained and possibly enhanced, as ecological impacts of environmental changes can be exacerbated in high-elevation habitats.

THE FIRST REPORTED POPULATION OF THE ERYTHRISTIC MORPH OF PLETHODON CINEREUS IN PENNSYLVANIA

Abstract The first record of the erythristic phenotype of the red-backed salamander (Plethodon cinereus) is reported from Pennsylvania at the southern edge of the glaciated plateau. The site in Elk County contains the highest population frequency of the red morph reported to date (47.4%).

Estimating Spring Salamander Detection Probability Using Multiple Methods

Abstract Many studies suffer from imperfect detection probability, i.e., species are not detected when individuals may be present. In occupancy studies, detection probability is often treated as a nuisance variable. When used as a primary variable of interest, detection probability can be examined as a function of sampling covariates with the goal of maximizing the probability of encountering target species. Efforts to determine which methods maximize detection probability will benefit monitoring programs, particularly for species that are difficult to detect. We used three sampling methods, leaf litter bag (LLB) surveys, visual encounter surveys (VES), and flip and search (FS) methods to detect larval Spring Salamanders (Gyrinophilus porphyriticus). We estimated occasion-specific estimates of detection and used an analysis of variance to determine if detection probability varied among sampling methods. We found the FS method yielded higher detection estimates than did the LLB and VES. In addition, occupancy estimates derived from FS sampling changed drastically when compared among other single-method models, suggesting that LLB and VES gave biased estimates of occupancy related to a low probability of detecting Spring Salamanders at occupied sites. Furthermore, our results suggest the FS method provided higher detection probability estimates as compared to estimates derived from models that combined all sampling methods. In conclusion, efforts to monitor Spring Salamanders should rely on FS for sampling populations to maximize detection probability to reduce costs and increase effectiveness for large, widespread research projects.