Sea Circle

The white-spotted pufferfish (Torquigener albomaculosus) is known for its unique and complex courtship display. Males create large geometric circles in the sand to attract females for copulation. To construct the ornate circular structure, a male works for more than a week straight. He flaps his fins along the seafloor to build ridges which he then decorates with shells and coral and sculpts a unique maze pattern in the center where a female might lay her eggs if, after evaluating his construction skills, she chooses him. He guards the eggs until they hatch and does not reuse the circles. The geometric circles were first noticed by divers in 1995, but it was not known that they were created by white-spotted pufferfish until 2013, when the species was discovered in the Ryukyu Islands. It was thought that white-spotted pufferfish are the only species to engage in this type of mating ritual, although in 2018, similar structures were discovered in Australia which may be built by a different species of Torquigener.