Mountaintop removal mining and valley filling (MTR/VF) is the most common form of land conversion in Central Appalachia and threatens the integrity of stream ecosystems. We investigated the effects of MTR/VF on stream salamander occupancy probabilities and overall community structure by conducting area constrained active searches for stream salamanders within intermittent streams located in mature forest and those impacted by MTR/VF. During the spring and summer of 2012, we detected five stream salamander species (Desmognathus fuscus, D. monticola, Eurycea cirrigera, Pseudotriton ruber, Gyrinophilus porphoriticus) and, using a hierarchical Bayesian analysis, found that occupancy probability was greatly reduced in MTR/VF streams compared to control sites. Additionally, the salamander community was greatly reduced in MTR/VF streams; species richness estimates for MTR/VF streams was approximately 2.1 (± 0.5 s.e.), whereas richness was 4.8 (± 0.2 s.e.) at control streams. Numerous mechanisms may be responsible for decreased occupancy and diminished salamander communities at MTR/VF streams; though water chemistry at field sites may be a particularly important mechanism. Indeed, we detected elevated levels of conductivity, pH, and dissolved metals and solids in MTR/VF streams. Our results indicate that salamander communities, along with many invertebrates, fish, and other aquatic and/or semi-aquatic animals, are extremely susceptible to MTR/VF mining practices.
Dept of Forestry, University of Kentucky, Lexington, KY
P71 • Joel M. Gramling, Zachary J. Brownlee
The Short Term Effects of Laurel Wilt on Native and Non-Native Coastal Plant Species
Laurel Wilt is a disease caused by a fungal pathogen that is thought to have been introduced to the United States from eastern Asia. The primary vector for Laurel Wilt, the redbay ambrosia beetle, was first collected at Port Wentworth near Savannah, Georgia in 2002. In the last 12 years the disease has spread across the southeastern United States affecting numerous species in the Lauraceae plant family. In 2008, vegetation plots were established along coastal North and South Carolina to monitor the progression of this disease as it moved up the Atlantic coast and to quantify changes in coastal plant communities. Analysis of plot data collected annually (2008-2013) has indicated that the disease is significantly more likely to affect larger diameter stems (> 5 cm) than smaller diameter stems (< 5 cm) of lauraceous plants. Additionally we have quantified changes in basal area and stem number of plant species in coastal plant communities of the Carolinas. Our results suggest that the short term effects of Laurel Wilt are not facilitating an increase in invasive species abundance or establishment. Instead, native plant species already present in the plant communities are occupying spaces that are no longer being taken up by lauraceous plants whose number and biomass have been significantly reduced by Laurel Wilt.
Dept of Biology, The Citadel, Charleston, SC
P72 • Trent D. Smith, Timothy O. Menzel
An Investigation of Possible Mechanisms Behind the Behavioral Responses of Aphaenogaster carolinensis to Other Ant Species
Previous studies have shown interspecific interactions involving Aphaenogaster carolinensis vary depending upon the identity of the other species involved. The specific behaviors of A. carolinensis during these interactions have not be investigated. This behavior was isolated during field observations of A. carolinensis on bait cards containing a food sources and one of three other ant species or no ant control. Two sets of variables were quantified from video recordings of these observations. The first set was collected at the bait card level and included angular distances from entry to exit and from both entry and exit to treatment (specimen or empty control), time on bait, distance traveled and average speed. These were analyzed together for a nonrandom relationship with treatment using a Multiple Response Permutation Procedure (MRPP). The second set of variables, at the within bait level, included speed at specific points on baits and distance to treatment from those points. Effect of treatment on speed, the relationship between distance to treatment and speed, and the interaction between treatment and distance were analyzed using ANCOVA. The relationship between bait card level variables and treatment was not different from random (ObservedDelta=0.3999, ExpectedDelta=0.3963, p=0.5242). The within card relationship between treatment and speed was significant (df=3, F=5.763, p=0.0009) while the effect of distance to treatment (df=1, F=0.427, p=0.5142) and the interaction between distance and treatment (df=3, F=2.148, p=0.0962) were not. We conclude that A. carolinensis’ behavior within the spatial area of baits may depend on the species they are in contact with.
Dept of Natural Science, Piedmont College, Demorest, Georgia
P73 • Megan E. Gibbons1, Karen M. Warkentin2, Jennifer Stynoski3
Genetic and Non-Genetic Factors Influence Development and Behavior of Red-Eyed Treefrogs
Plasticity in transitioning from one life stage to the next can be adaptive for species with complex life-cycles, particularly if conditions across life stages are unpredictable. Genetic and non-genetic maternal effects may influence the outcome of the niche shift, with responses varying between individuals. The red-eyed treefrog (Agalychnis callidryas) is an excellent study organism for investigating genetics and life-stage switch point timing because embryos exhibit adaptive phenotypic plasticity in hatching time and females deposit multiple clutches of eggs in a single reproductive event, allowing for manipulation of mates. In this study, we investigated the how hatching time, maternal effects, and paternal (i.e., genetic) effects influence antipredator behavior and development of tadpoles, and developmental traits of metamorphs, including larval period, body size, and jumping ability. There were no maternal or paternal effects on tadpole behaviors in antipredator trials, although hatching time influenced some of the behaviors. Early-hatched tadpoles were significantly larger than late-hatched tadpoles 21 days after oviposition, and tended to have shorter larval periods. There were significant maternal and paternal effects on developmental traits of metamorphs, and several traits in which a significant interaction between maternal and paternal effects suggests genetic dominance. As additional evidence for maternal effects, we found that offspring of females that produced larger eggs had shorter larval durations, were larger at metamorphosis, and had longer jumping distances. This study indicates the potential importance of single early-life events on subsequent life stages and that some of these effects are dependent on maternal and genetic factors.
1 Birmingham-Southern College; 2 Boston University; 3 Organization for Tropical Studies
P74 • Nick W. Spalsbury, Jim Welch, Richard Phillips
