Plants
Animals
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PROJECT DESCRIPTIONS Mapping the distribution of canopy trees In order to provide an initial description of the habitat diversity in the Furman Forest, Dr. Wade Worthen began a survey of canopy tree species in Summer 2008. He has established a grid of over 500 sampling points, with 100 m between all points. At each point, all trees within an 8 m radius of the point greater than 2 cm in diameter are sampled; the species and size (diameter at ~ 1.5m) are recorded. These data will provide a description of how canopy tree communities change with elevation, proximity to watercourses, and land use history. Thiry-two species have been found so far. Of immediate interest is the infestation of wooly adelgids (sap sucking insects) that are killing Eastern Hemlock (Tsuga canadansis) trees. None of the hemlocks sampled thus far are free of adelgids. Other noteworthy observations are: 1) surprizing densities of American Chestnut (Castanea dentata) saplings, sometimes reaching heights of 5-7 m; and 2) a Northern Red Oak (Quercus rubra) with a diameter of 1.20 m - close (if not surpassing) the largest Northern Red Oak in South Carolina. This data set will also be analyzed with GIS technology, to look at the spatial patern to diversity and the relationships among and between different species of canopy trees.
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Seasonal change in the herpetofauna at two elevations As his Independent Research Project (BIO 502), Ben Delancey is conducting an experiment on the seasonal changes in the amphibians and reptiles using refugia at two elevations. Plywood coverboards (1.3 m x 1.3 m) were used as experimental refuges. Ten coverboards were placed along 4 transects, at 20m intervals. Two transects were in the Tryon watershed and two were in the Landrum watershed. In each watershed, one transect was placed at ~500m in elevation and one transects was placed at ~650 m of elevation. Ben has been checking each coverboard at least once a week, recording all reptiles and amphibians and also measuring soil temperature beneath the coverboard. Ben is testing the hypothesis that these ectothermic organisms will move up in elevation along these south facing slopes as fall proceeds. Ben has also been conducting a survey of herpetofauna (reptiles and amphibians) in Furman Forest, and is responsible for finding and photographing the specimens depicted in the taxonomic surveys section of this site.
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Microhabitat differences among Desmognathus salamanders The deep moist woods of the Southern Appalachian mountains is the worldwide center for salamander diversity; more salamander species occur in this bioregion than any other place in the world. Several species in the genus Desmognathus co-occur in mountain streams, including Desmognathus monticola, D. fuscus, D. ochrophaeus, and D. quadramaculatus. In a secondary research project, Biology major Ben Delancey is describing how the ecological niches of these species might differ. There are several drainages in the Furman Forest area, each with the typical stream structure of pools, riffles, and runs. Ben samples an area by flipping rocks until he locates a salamander. He catches it, measures its length, and identifies it to species. Then he measures water depth, depth of depression, distance from bank, distance from water, and other ecological variables. Ultimately he will use Discriminant Function Analysis to determine if these species differ in their habitat use with respect to these variables.
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Perch selection by dragonflies In 2005 and 2006, Dr. Wade Worthen and Biology major Christopher Jones conducted experiments examining the relationship between perch height and body size in dragonflies. Perches are very important for defending territories and acquiring mates, so perch use is an importatn aspect of dragonfly biology. The two ponds on the Blue Wall Preserve (within the Furman Forest area) were included in this study, in addition to ponds at Bunched Arowhead Preserve in Travelers Rest, Furman Lake on the campus of Furman University, and an impoundment with the Sumter National Forest in Union County, SC. Worthen and Jones (2006, 2007) found that perch height was significantly correlated with body size; small dragonflies use low perches and larger dragonflies use progressively taller perches. This pattern could be due to aerodynamic constraints on dragonflies. As dragonflies increase in size, the mass increases as a cubic function of length but the surface area of the wings only increase as a squared function of length. So, the mass carried by each unit of wing surface area increases with body size; this is called "wing loading", and it must be offset by thrust in order for flight to be achieved. Thrust can be increased by headwind speed, which increases with height above the surface. So, large dragonflies may perch higher because they can fly more easily from taller perches where windspeed is greater. However, Worthen and Jones (2007) found no evidence for changes in perch height with wind speed, suggesting that wind speed is not contributing to perch height selection. Rather, larger species are competitively dominant in aggressive interactions for perches; larger species are more successful at displacing smaller species than the reverse (Worthen and Jones 2007). So, it appears that competition for perches contributes to the relationship between body size and perch height in dragonflies.
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