Diverse countermeasures for protection of cristaria plicata (a sort of shellfish) which died en masse in the sector of the Project on the Nakdong River and caused to investigation for that will be implemented. In the joint research by Busan Regional Construction Management Administration, Nakdong River Environment Administration and K-Water from April to July, the change of habitat environment turned out there was no big difference since filling weir with fresh water. Therefore, it was decided to maintain existing habitat instead of moving to other area. Also dredging work around the habitat was decided not to be done for species protection. Precise investigation was jointly fulfilled with expertise group in the Mijeon Stream (Zone 12, the Nakdong, on Feb 2) and the confluence of the Deokgok Stream (Zone 20, the Nakdong, on April 13) after the discovery of cristaria plicata’s habitat. After investigation on 10 spots of 2km from the downstream of the Deokgok Stream to the Hapcheon Weir, 120 and more plicatas were founded; also more or less were found in five tributaries including the Mijeon Stream and the Yangsan Stream. Concerning the death en masse in April this year, the investigators said that it seems out of temporary factors of lowered river level caused by dry season and dredging works. Busan Regional Construction Management Administration has a concrete plan for continuous management on the River by monitoring subtle changes of habitats, especially with special program on the upper stream area from the Hapcheon Weir where the species inhabit densely.
