Abstract
Oviposition sites of Buergeria japonica were surveyed in portions of two streams near the coast on Okinawa Island, Ryukyu Archipelago, Japan. Twenty-five and 52 oviposition sites were found. At all these sites the salinity was constantly 2‰ or less despite occasional exposure of these portions to the sea breeze. The pH value at the sites, ranging from 7.7-10.2, never dropped into the acid range. There were no significant differences in water depth or distance from the bank at the oviposition sites between the two streams, despite the prominent differences in some topographic characters, such as maximum water depth and stream width.
