We address the practical issue of using thermal image data without adjustment or calibration for projects which do not require actual temperatures per se. Large scale airborne scanning in the thermal band at 8.5-13 孠was obtained for a mangrove and salt marsh in subtropical eastern Australia. For open sites, the raw image values were strongly positively correlated with ground level temperatures. For sites under mangrove canopy cover, image values indicated temperatures 2-4àlower than those measured on the ground. The raw image was useful in identifying water bodies under canopy and has the potential for locating channel lines of deeper water. This could facilitate modification to increase flushing in the system, thereby reducing mosquito larval survival.