Abstract

Spawning site selection can strongly influence egg survival and the distribution patterns of species. Coastal areas are risky environments for breeding amphibians because the rate of egg survival falls drastically with increased salinity. The working hypothesis of the present study was that Buergeria japonica, a racophorid anuran inhabiting beach in coastal areas, avoids spawning sites with high salinity. I tested whether females of B. japonica select oviposition sites based on salinity levels. Amplexed pairs were collected in the field and introduced into a container with dishes as potential spawning sites, two with pure water and two with water of various salinities. With one exception, females laid significantly more eggs in pure water than in salinities greater than 1‰. Female B. japonica have an ability to distinguish salinity levels when laying eggs. Spawning site selection based on salinity seems to be important for frog species distributing in coastal areas to reduce egg mortality.