In situ spawning of a deep-sea vesicomyid clam: Evidence for an environmental cue

Spawning of the deep-sea vesicomyid clam Calyptogena soyoae was shown to be induced by short-term changes in water temperature. It was induced in situ by artificially increasing the ambient water temperature using the submersible Shinkai 2000 off Hatsushima Island in Sagami Bay, Japan. Furthermore, we recorded in situ spawning events associated with natural changes in temperature at a deep-sea observatory on 11 occasions over a period of 1.5 years at the same site. The potential benefit of thermal regulation of reproduction in an otherwise aperiodic, dark, and unstable environment suggests that this strategy may be common for reproduction, particularly near chemosynthetic communities.