STRUCTURE AND DYNAMICS OF THE ARBOREAL TERMITE COMMUNITY IN NEW-GUINEAN COCONUT PLANTATIONS

Whereas ant mosaics have been widely recognized and described in tropi cal ecosystems, data on space partitioning among arboreal termite colo nies are rudimentary. During a long term field study in New Guinea, th e distribution of arboreal termite species in coconut plantations as w ell as the extent and dynamics of competition between them were invest igated. The three dominant species, Microcerotermes biroi, Nasutiterme s princeps and N. novarumhebridarum, feed on the same items but never exploit the same tree. The resulting distribution pattern is a mosaic with two peculiarities. First, some extended areas around N. princeps colonies appear unexploited, as this species practices interference co mpetition on a wide scale, defending large territories inter- and intr a-specifically. Second, interspecific relations are asymmetrical. In s ome plantations, large colonies of N. princeps expand their territory by destroying colonies of M. biroi, but when the pressure of N. prince ps is relaxed, dense populations of colonies of M. biroi can recoloniz e the trees in a few years' rime. Territorial boundaries may thus chan ge relatively fast. N. novarumhebridarum often colonizes dead trees an d interferes less with the other species. These facts are consistent w ith each species' reproductive investment strategy Hypotheses are prop osed to explain how the dominant species can coexist, even in long est ablished plantations.