Solving the Mystery of Reproductive Behavior in Reef Fishes

One of our research projects are on pufferfish that construct “crop circles.”


The white-spotted pufferfish Torquigener albomaculosus, which has a total length of 10 cm, inhabits areas with a sandy bottom off Amami-Oshima Island, Japan. We discovered that the males construct geometric circular structures measuring 2 m in diameter on the seabed by digging valleys with their fins and body. The males then mate with females at the center of these structures. This discovery has been reported with surprise worldwide. However, many mysteries remain about the ecology of the pufferfish and structure of these crop circles. For example, Q1: How do small pufferfish construct such elaborate circular structures without a ruler or compass?; and Q2: What is the most important feature of the circular structure that influences the choice of the female mate?


To help address these questions, we are seeking collaborators to study the ecology of the pufferfish and structure of the crop circles. Additionally, any information regarding underwater observation sites of pufferfish of genus Torquigener is welcome.