Early Developments of Artificially Reared Colonies of Camponotus japonicus MAYR (Hymenoptera, Formicidae)

Six dealate queens, captured in May 1990 at Mito, central Japan, were experimentally reared in small boxes, and the founding and subsequent development of colonies were observed for two seasons. After the first group of workers emerged, the colonies were fed with dead bodies of a calliphorid fly, Lucinia sp. and raw sugar. Four colonies succeeded in producing workers and had an average of 18 workers and 14 larvae by the end of the first season. In April 1991, the colonies were started with the same condition, i.e., each with 15 workers and 10 larvae. They were fed with different amounts of fly, i.e., colony A with 37 mg/day in dry weight, B with 18.5 mg/ day, C with 3.7mg/day and D with 1.2mg/day. Changes of worker population until December (+280 in colony A, +103 in B, -1 in C and -9 in D) were highly correlated (r=0.998, p<0.001) with the amount of food given. The result suggests that about 4mg/day of dry flesh are necessary for sustaining incipient colonies with some 15 workers. Soldiers (major workers) were reared in colonies A and B since July of the second season, when they had about 30 workers.