The Defense Facilities Administration Agency said Tuesday it has found a rare sea mammal in waters east of here during a survey of the sea off Okinawa.

Agency officials said they spotted a 3-meter dugong about 1,500 meters off the east coast of Nago, the site for the relocation of the heliport functions of the U.S. Futenma Air Station.

The spot where the dugong was seen was about 10 km northeast of the planned site and this siting of the rare sea mammal could affect the relocation issue.

The agency has been conducting an aerial survey since Oct. 30 to determine the number of dugongs ahead of the planned relocation.

The survey is in line with recent resolutions by the Switzerland-based World Conservation Union and the Nago city assembly to protect the rare sea mammal.