Tsurigasaki

Tsurigasaki is the flagship nudibranch site of Sagami Bay, a broad rocky reef from 5 to 20 metres colonised by dozens of hydroid and bryozoan species that in turn support extraordinary nudibranch densities. Local guides tally over 80 nudibranch species at this single site, including cold-water specialists like Flabellina, Trinchesia, and Cuthona genera that require water below 18 degrees Celsius. Wobbegong sharks rest wedged into crevices along the reef base, and juvenile cuttlefish aggregate in the kelp fronds from March through May. Visibility is best in winter when plankton blooms subside and the cold water stratifies cleanly.