Press Release

July 6,2011

Incorporated Administrative Agency, Fisheries Research Agency

Sea reserve near Iriomote Island confirmed as important spawning ground of Epinephelus ongus
? Succeeded in photographing the instance of spawning in water ?

Epinephelus ongus (family Serranidae), caught off the Yaeyama Islands, are an important coastal fishery resource in the subtropics. The Yonara Channel lying between Iriomote and Kohama Islands is a known spawning ground of this species. Based on experience, local fishermen have identified the zones and season that should be closed to fishing and have voluntarily avoided fishing of spawning schools.

The Seikai National Fisheries Research Institute of the Fisheries Research Agency has investigated the effects of protecting the spawning ground jointly with the Ishigaki Branch of the Okinawa Prefectural Fisheries and Ocean Research Center since 2010 and discovered that there is a spawning ground of E. ongus in the voluntary no-fishing zone. The parent fish start gathering at the ground several days before the specific spawning day of the year, spawning starts at around 11 o’clock at night and lasts less than an hour. A large number of fish eggs, likely to be those of E. ongus, were also collected during the same period.

The findings verified the effectiveness of protecting the spawning ground; and by analyzing the sea current during the spawning time, it is possible to estimate the direction in which the spawned eggs would move and the area where they would end up. The estimation and protection of spawning and nursing grounds will greatly contribute to the restoration of the E. ongus resource.


Epinephelus ongus