The mode of feeding behaviors of termites were investigated by monitoring the acoustic emissions (AEs) generated from the wood under their attacks, as it had been revealed that the generation of AE events was evidently relevant to the activities of feeding.
The AE events began to generate from the wood specimens coexisted with termites of Coptotermes formosanus at about a few hours to more than ten hours after setting of the tests, and increased rapidly. After then they decreased and kept a constant rate for a while, and again they increased at about a few days after starting of the tests. The AE event rate repeated the cycles of increase and decrease periodically. Even with the same number of inhabiting workers, AEs were generated at higher rate from the specimen with soldiers than without soldiers. It was suggested that the feeding activities were accelerated by soldiers who were fed on workers. AE events decreased as the ambient temperature fell from the degree of 27°C and stopped at 12°C. AEs were generated again after rising of the ambient temperature, and continued to increase with ascending temperature until 36°C. After that, AE events decreased and stopped at more than 40°C, and they were no more detected even the ambient temperature were fell down again. The generation of AEs dropped or stopped by the exposure to lighting, suggesting that the activities of feeding of the termites were influenced by irradiation of light. The AE events began to generate once again even from the wood specimens under the exposure of lighting after a while.

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