Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/30/2006
Publication Date: 8/4/2006
Citation: Vogt, J.T., Wallet, B. 2006. Modeling dynamic thermal properties of imported fire ant mounds. Meeting Abstract.
Technical Abstract: Ground-based thermal infrared imagery, 3-dimensional modeling, and spatial analyses were used to model daily fluctuation in the temperature of imported fire ant mounds and their surroundings. The thermal center of the mound moved in a predictable fashion from east-southeast to west-southwest during the course of the day. Time of day, sun elevation, and ambient temperature were all significant predictors of mound temperature and surrounding temperature. Mound temperature response to predictive variables was generally faster than that of the surrounding area. Additionally, mound temperatures were more variable than those of the surrounding area, supporting the hypothesis that the fire ant mound acts as a solar collector, increasing temperature variability and allowing the colony to selectively occupy areas of favorable temperature within the mound. On average the south facing aspect of mounds was 22 percent larger than the north facing aspect, and the apex of the mound was offset about 80 mm to the north-northeast. Mound shape was related to surface temperature, with south facing aspects warmer than north facing aspects. These data will be used to build artificial templates for automated mound recognition in aerial thermal infrared imagery.