To study individual participation in tunneling excavation, each of 27 workers (plus three soldiers) of Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was identified with a unique marker and released in a two-dimensional arena provisioned with moistened sand, and their time budgets in excavation were recorded by a camcorder. We found that ≈20% of workers were excavating at any given time. Termites did not work in shifts, and only one or two specific individuals tunneled continuously throughout the 4-h observation. The majority spent <1 h in tunnel excavation, and ≈16% of workers never excavated sand. A positive correlation was found between excavation time and worker's antennal segment count which refers to a worker's age. However, a large variation in excavation time also was recorded among workers with same antennal segment number. Thus, worker age might not be the only determining factor for tunnel excavation load in the Formosan subterranean termite.