Abstract
Eight years’ fluctuations of fruit production were studied in a warm temperate broadleaved forest on Yakushima Island, southern Japan. Eight tree species characterized by sapfruits or capsules were studied, and all of them were regarded as animal dispersal. Total numbers of sapfruits fluctuated remarkably in eight years for each species. Cleyera japonica and Eurya japonica bore fruits every year constantly and fruiting fluctuations were less remarkable than the other species. Ternstroemia gymnanthera and Symplocos prunifolia seemed to bear fruits many or few in the alternate years. Fruiting fluctuations of Ardisia sieboldii, Myrsine seguinii, Litsea acuminata and Vaccinium bracteatum were great; they had few fruits in several consecutive years. The mean temperate of the preceding August was correlated with fruiting number of only C. japonica and the total sunshine time of the preceding August was correlated with fruiting number of C. japonica and M. seguinii. Fruiting fluctuation was also influenced by typhoon. A poor crop of V. bracteatum and A. sieboldii had continued after the damage that trunks or branches were broken by typhoon attacked in 1990. For every species except T. gymnanthera and L. acuminata, great fruiting years tended to coincide among individuals within a species. As for inter species, great fruiting years also synchronized mildly.
