Date of Award
Master of Science (MS)
Forestry and Environmental Conservation
Brandon K Peoples
Troy M Farmer
Jean K Leitner
Bartram’s Bass Micropterus sp. cf cataractae is endemic to the Savannah River basin of South Carolina and Georgia. Bartram’s Bass is threatened by habitat alteration and hybridization with invasive Alabama bass (M. henshalli) and other non-native co-occurring congeners. This study aimed to identify reproductive habitat preference of this species, and factors contributing to its occurrence.
In Chapter 1 we identified Bartram’s Bass nesting preference throughout the upper portion of its native range. In spring/summer 2017 and 2018, snorkel surveys were performed in tributaries to quantify nesting microhabitat use of Bartram’s Bass. Zig-zag transects were used to locate nests and to quantify habitat availability. Nesting microhabitat parameters were recorded at each nest detected, and eggs were collected for genetic analysis. Average velocity at the 39 pure Bartram’s Bass nests observed was 0.09 ± 0.02 m/s, SD, lower than average available velocity of 0.22 ± 0.01 m/s, SD (p= 0.0028). Average depth of nests was 0.70 ± 0.04 m, SD and was similar to those available 0.67 ± 0.02 m, SD (p= 0.6946). The substrates used in nests during both breeding years combined were primarily silt (36%), cobble (31%), and gravel (21%), whereas the most available substrates observed in transects were bedrock (23%) and cobble (23%) (P
In Chapter 2 we determined the relative importance of abiotic factors and distance from reservoirs for predicting occurrence of Bartram’s Bass. From March to November of 2017 and 2018, individuals were collected from 160 sites across the upper Savannah River basin. Sites represented a gradient of key abiotic variables—watershed- and riparian-scale land use types, ecoregions, stream gradient, and elevation. Genetic analysis of 241 individuals from 50 sites revealed Bartram’s Bass were present at 33 sites, and hybrids were present at 21 sites. Conditional inference trees were used to predict the variables that drive Bartram’s Bass distribution. Forested land cover at the watershed scale was the most significant predictor of Bartram’s Bass presence (p=0.0236). Pure individuals preferred sites of greater than 75% forested cover (p
Judson, Emily Elizabeth, "Conservation of Endemic Bartram's Bass: Nesting Microhabitat Use and Spatial Distribution with Congeners in the Savannah River Basin" (2018). All Theses. 3255.