Submitted to: Biennial Workshop on Aerial Photography, Videography, and High Resolution Digital Imagery for Resource Assessment Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/2/2005
Publication Date: 2/1/2006
Citation: Vogt, J.T., Wallet, B. Daily fluctuations in imported fire ant (Solenopsis spp., Hymenoptera, Formicidae) mound surface temperature. Biennial Workshop on Aerial Photography, Videography, and High Resolution Digital Imagery for Resource Assessment Proceedings. Weslaco, TX, October 4-6, 2006.
Interpretive Summary: Airborne thermal imagery is a potential tool for detecting imported fire ant mounds in aerial imagery. Researchers in the USDA, ARS Biological Control of Pests Research Unit, in collaboration with Cooperative Research and Development Agreement partner Automated Decisions, LLC, developed new analytical tools to characterize daily changes in mound surface temperature. The researchers are the first to discover and document changes in the “hot spot” of mounds over time. This discovery will lead to new methods to automatically classify fire ant mounds in aerial imagery, which will save researchers and regulatory personnel time and money as they map fire ant populations over large areas.
Technical Abstract: The USDA, ARS Biological Control of Pests Research Unit is partnering with Automated Decisions, LLC under Cooperative Research and Development Agreement to develop techniques for identifying and quantifying imported fire ant mounds in remotely sensed data. Preliminary observations using thermal infrared imagery on the ground and from a ground-based platform (bucket truck) indicated that imported fire ant mounds tend to heat up more quickly than their surroundings in the morning, and cool more quickly than their surroundings in the evening. The goal of the current study is to characterize daily fluctuations in mound surface temperature to provide data necessary for automated detection of mounds in aerial thermal infrared imagery. Data will also be used to formulate hypotheses regarding daily movement of imported fire ant colonies within mounds. The temperature-weighted centroid of imported fire ant mounds was highly variable along the east-west axis of thermal infrared mound images, and moved in a predictable fashion along the north-south axis of the images. These results indicate that shape analysis of thermal imagery of fire ant mounds has the potential to yield crucial information for automated detection of mounds in airborne thermal imagery.