A US spy ship was spotted early this month off the military port of the northeastern town of Suao at a distance close enough to be identified with binoculars, defense sources said yesterday.
The ship was identified as the USNS Bowditch. The ship is claimed by the US Navy on its Web site to be an ocean survey vessel engaged in hydrographic studies.
The ship's presence off Suao in early May might be connected to Taiwan's annual Hankuang military exercises, held in the same area.
A defense official, who spoke on condition of anonymity, said the ship might be in the area to test the Taiwan military's response; it might also be executing some sort of surveillance mission.
The Bowditch is one of about 20 such ships deployed by the US Navy around the world, defense sources said.
The Bowditch is usually cruising in the Asia-Pacific region and its main task is spying on China.
There have been several run-ins between the ship and Chinese warships or fighter planes in recent years. Despite protests from China, the ship sails along China's coastline on a regular basis.
The ship sails only in international waters but China nevertheless has frequently sought to intercept the Bowditch and force it away from its shores, claiming that the ship is violating China's "exclusive economic zone."
China has recently changed its tactics against the Bowditch, now using fishing boats to deliberately bump into the US vessel as a way of scaring it off.
The Bowditch suffered some damage in one such intentional crash earlier this year.
A defense source, who has extensive knowledge about the operations of the Bowditch, said China is desperate to get rid of the Bowditch because the ship is equipped with state-of-the-art equipment capable of producing three-dimensional underwater maps of the seas it has surveyed.
"It is not known how much the ship has done in its underwater mapping in the region. If all the underwater maps concerning waters off China have been completed, the day might come when China's submarines would have no place to hide," the source said.
"The US Navy had sent delegates to Taiwan last year seeking provision of a port for the repair and maintenance of Bowditch-type spy ships," he said.
"Keelung was the first choice, but it did not have facilities large enough to accommodate the US spy ships. Tsoying was the best choice but was not chosen because of its distance," he said.
Despite constant operations off Taiwan, Bowditch-type spy ships do not have any cooperation with Taiwan's navy. The high-tech underwater mapping technology of the ships is still beyond the reach or understanding of the military here.