Friday, August 16, 2019
Exhibit Hall, Kentucky International Convention Center
Benjamin Tobin, Kentucky Geological Survey, University of Kentucky, Lexington, KY, Benjamin Farmer, Biology, University of Kentucky, Lexington, KY, Benjamin Miller, Lower Mississippi Gulf Water Science Center, US Geological Survey, Nashville, TN and Adia Sovie, Wildlife Ecology and Conservation, University of Florida
Background/Question/Methods: Cave environments provide a unique opportunity to understand patterns of speciation. Fragmentation and unique physical structure of caves result in high endemism. Karst groundwater dissolves the bedrock to create a network of interconnected passages, resulting in a myriad of potential ecological niches. However, the connection between current and past groundwater flow and cave ecosystem composition is poorly understood. To address this, we used biological inventory data from 30 caves in Sequoia and Kings Canyon National Parks, conducted a pair-wise Jaccard Analysis along with linear regression models to determine which combination of spatial variables best explained patterns in (1) species richness and (2) species composition of each cave.
Results/Conclusions: Results indicate that lower elevation caves that are in larger bands of marble (a metric of habitat availability) have higher species richness and lower endemism while caves that are in smaller bands of marble and at higher elevations have lower richness and higher endemism. Patterns in surficial habitat only account for a small portion of the variability seen in species richness and endemism. This is likely a result of variable habitat connectivity that results from geologic controls on groundwater movement, which are often independent of surface expressions of underground habitat. Metrics of habitat availability and connectivity improve our understanding of both endemism and species richness. These results suggest that past and current geologic controls on groundwater flow are a driving force in cave ecosystems.
