Climate can affect the growth of vegetation in white-tailed deer habitats, in turn affecting the nutritional status of deer. Because antlers also indicate the overall health of the individual white-tailed deer, variation in weather from year to year could result in a measureable difference in the antler growth. We analyzed the effects of weather on antler growth of all white-tailed deer harvested from 1983-2012 from 20,234 ha of hunting grounds at Quantico Marine Corp Base, Virginia. We analyzed the right beam diameter at the base and right beam length measured for each antlered buck taken against heating degree days (Dec. 1-Feb), growing degree days (March 1-Aug. 15), and precipitation levels (March 1-Aug. 15) prior to harvest. We found a correlation between overall antler growth and the weather prior to and during each antler growing season with variation among age classes. Wildlife managers could use the relationship between weather and antler growth as a predictive tool for harvest management and as an indirect measure of habitat health.
Effects of Agricultural Practice on Mammal Diversity
Wildlife habitat is increasingly being converted to agricultural land to meet the demands of a growing human population. Determining how different agricultural practices will influence biodiversity is thus critically important. Although significant literature has explored the relationship between farming practices and insect diversity (particularly for pests and pollinators) less work has focused on the impacts of farming practice on vertebrate species. We are investigating the relationship between specific agricultural practices (including pesticide use, farm size, and crop diversity) and mammal biodiversity (measured through species diversity, abundance, and Shannon Index) on farms throughout the Piedmont of NC. We are collecting mammal samples from fifteen farms in Central North Carolina. Twenty Sherman live traps and three Bushnell Trophy Cams will be used at each site to measure both small and large mammal diversity. We have collected preliminary data from two study sites, but will continue sampling through June 2014. Sampled species to date include the white-footed mouse, hispid cotton rat, white-tailed deer, and Virginia opossum. Results will be analyzed using a MANOVA. Use of pesticides is anticipated to be correlated with lower mammal diversity, and high crop diversity with the higher mammal diversity. Results aim to inform future agriculture in a direction that facilitates the greatest natural biodiversity, thus preserving ecosystem services. Due to its demonstrated interest in boutique agriculture, North Carolina is excellent candidate for applying this study’s findings.
Environmental Studies, Elon University, Elon, NC
P83 • Heather M. Joesting1, Patrick D. Biber2
Potential Use of Shrimp Biofloc Solids as an Alternative Fertilizer in Coastal Salt Marsh Plant Nursery Production
The large nutrient inputs required to support high stocking densities in shrimp culture contributes to the accumulation of biofloc particles. Although these particles are beneficial to shrimp and nutrient cycling, management of biofloc concentration has been shown to significantly enhance shrimp production. To increase sustainability and investigate the potential for supporting an additional crop, a means of nutrient reclamation from removed biofloc should be considered. This study examines the potential use of shrimp biofloc solids as fertilizer for the production of salt marsh plants used in coastal restoration. Spartina alterniflora and Juncus roemerianus individuals were maintained in a greenhouse and assigned to one of three weekly dosing treatments for a six week dosing period: (1) control with no nutrient additions (2) addition of Miracle-Gro™, and (3) addition of dried, ground biofloc solids. Plants were measured at the end of the dosing period and approximately three months after the final dose (response period) for plant biomass and tissue nutrient content, and control plant productivity was compared to Miracle-Gro™ and shrimp biofloc solids independently. Results indicated that although shrimp biofloc solids had ~2.5 times greater total nitrogen content, plants treated with Miracle-Gro™ had greater overall plant productivity compared to the control than biofloc solids in both dosing and response periods. However, increased plant biomass and tissue nutrients in plants treated with shrimp biolfoc solids compared to the control did suggest fertilization potential for shrimp biofloc solids in nursery production of salt marsh plants.
1Dept of Biology, Armstrong Atlantic State University, Savannah, GA; 2 Gulf Coast Research Laboratory, University of Southern Mississippi, Ocean Springs, MS
P84 • Kristen S. Gillespy, Emily S. Rademacher, Maximilian M. Kern, Leigh Anne Harden, Shannon E. Pittman, Michael E. Dorcas
Factors Affecting Detection Probability of Spotted Salamanders (Ambystoma maculatum)
Monitoring wildlife populations using mark-recapture is valuable for estimating population size and structure. Information about population statistics is critical for amphibian conservation, which is important for sustaining diverse ecosystems. However, factors affecting detection probability can skew population size estimations and measures of other demographic parameters. We used the spotted salamander (Ambystoma maculatum), a cryptic wetland amphibian, as a model species to investigate factors affecting detection probability. Secretive wetland species that use aquatic habitats to breed are ideal organisms for mark-recapture studies because a large portion of the population arrives at one centralized location to reproduce. Additionally, wetland species serve as indicators of wetland ecosystem health. We monitored A. maculatum entering and exiting a 0.5 ha ephemeral wetland in the North Carolina Piedmont area using 40 aquatic funnel traps and a 400 m drift fence containing 76 terrestrial pitfall traps spaced 10 m apart positioned on both the inside and outside of the fence. Traps were checked daily during January and February 2013 and 2014. Individuals were identified using elastomer codes and an individual spot recognition code system. We used program MARK to investigate factors (e.g. sex, trap type, and behavioral response to traps) that affect detection probability and contribute to imperfect detection. We constructed candidate models that included these factors as covariates and used AIC to evaluate the most parsimonious models. Our findings suggest that it is important to consider various factors affecting detection probability when assessing population demographics of a secretive species.
