Melissa Dickinson, Assessment Of Small Mammal Populations In Two Southeastern Forests Of Big Ridge In Chattanooga, Tennessee
Faculty Chair: Dr. Timothy Gaudin
Field research was conducted to test for effects of urbanization on small mammal abundance and diversity. Preliminary studies were performed to test sampling techniques and acquire a sample size estimate for the primary study. Sampling sites were chosen in old growth and mixed hardwood forest areas. Six day sampling periods consisted of differing densities and setups of Sherman and pitfall traps within 0.16-ha plots. Data was not statistically analyzed due to minimal sample sizes.
Comparable 1.28-ha mixed hardwood forest study sites were chosen in the Big Ridge area of Chattanooga, Tennessee for the primary study. One site had protected status, whereas the other was characterized by urbanized development. At each site, five randomly selected 0.16-ha plots containing 20 small mammal traps were sampled dally for 14 days. Small mammal relative abundance and habitat data were analyzed using a paired t-test and two-sample t-test, respectively. Pearson's correlation analysis was performed to identify any relationships between small mammal abundance and habitat characters. Mean relative abundance was found to be significantly higher (P=0,0005) in the unprotected site. There was significantly greater (P=0,03) vegetative coverage in the unprotected site, but the correlation analyses yielded no significant relationships (P>0,10) between abundance and vegetative coverage. In conclusion, the significantly higher small mammal abundance found at the unprotected site is most likely a result of increased coverage in the unprotected area, There a significantly higher percent of vegetation in the unprotected site and the mean percentages of coarse woody debris and artificial debris were higher as well, although these latter differences were not statistically significant.