Pop-up Archival Tags Used to Survey the Ecology of Kwangtung Skates

West Sea Fisheries Research Institute, NFRDI released kwangtung skates (Raja kwangtungensis) with pop-up archival tags on them off Heuksan island in the West Sea on May 21, 2010 to survey the species\' ecological conditions such as temperature and migration route. The institute announced that it will have another release of its kind off Daecheong island, located northern most in the West Sea on May 28.

The small-sized pop-up archival tag which was used for the survey was first adopted in Korea for this project. The device is designed to record every 10 seconds water depth, temperature and illumination for a 3 month period until it detaches to float to the sea surface.

The buoying tags send recorded data via a satellite to the lab of West Sea Fisheries Research Institute, where the data gets analyzed to predict habitat temperature, depth, growth rate and migration route of kwangtung skate.

The institute has conducted since 2007 the tagged release of kwangtung skate as part of resource rehabilitation program. For the program, as many as 926 individuals of kwangtung skate put on by 13cm long traditional tags looking yellow noodle were released in the waters around Heuksan and Daecheong islands.

The traditional tag has its identification code and lab\'s phone number on it so that recaptured skates can be returned to the lab. However, it turned out to be less effective because the tagged skates were less likely to be caught and it was not possible to figure out what happened after the fish were released.

To improve the survey, the lab adopted the electronic tag and plans to continue the survey until the species is successfully recovered. Fishers are advised to release the fish after recording identification code and catch location if they recapture the tagged kwangtung skates.