Connect with us

Politics & Security

Senkaku Islands First Environmental Survey Using Drones Carried Out

Four Chinese ships entered the area while the Senkaku Islands survey was in progress, forcing the Japan Coast Guard to surround and protect the research vessel.



Senkaku Islands
A research team from Tokai University pilots a drone during an aerial survey of Uotsuri Island, one of the Senkaku Islands. January 30. (© Sankei by Hiroshi Kawase)

A university research team carried out Japan’s 1st environmental survey by drones of one of the Senkaku Islands, despite attempts by unwanted visitors to interfere with the effort.

On January 29 and 30 a shipborne research team used a drone to survey Uotsurishima from the air. Environmental degradation had been feared due to overgrazing by wild goats and other factors. 

Ishigaki City municipal authorities, who administer the Senkaku Islands, wanted the drone images to help clarify current conditions there. 

Vegetation Loss, Ocean Debris Discovered by Drone Survey

An oceanographic research team from Tokai University headed out from the Port of Ishigakijima toward the Senkaku Islands. Onboard the 997-ton Shinsei Maru, a marine research vessel, they were carrying out environmental surveys. Also aboard were Ishigaki City Mayor Yoshitaka Nakayama and members of the Ishigaki City Council. In addition, a Sankei Shimbun reporter joined for the first time. 

On January 31 Mayor Nakayama held a press conference to discuss their observations. 

"It looks like there is even less vegetation left compared to the situation at the time of an earlier survey," the mayor said. (A previous survey was conducted 11 years earlier.) He also indicated that officials realize the need to go ashore to conduct a full-scale survey.

This recent survey followed up one the city carried out in 2022. However, this was the first instance in which drones were used. In this case, drones surveyed the island and surrounding waters, collecting data for the purpose of environmental protection.

Senkaku Islands
The Tokai University research team checks images sent from a drone to the research vessel on January 30. (© Sankei by Hiroshi Kawase)

The research ship also collected data on salinity and other ocean conditions at several locations. This was part of an investigation of the water quality of the sea in the area.

On January 31, Ishigaki City made public some of the images and other data collected. 

Tokai University professor Yoshihiko Yamada, an expert on maritime policy in the Department of Maritime Civilizations, headed the survey team contracted by the city. 

According to Professor Yamada: "The aerial survey clearly shows that compared to a year ago there are fewer trees and (soil) slumpage has progressed." He also confirmed the observation of "a lot of ocean debris" in the immediate area.

Intrusion and Provocation by China Coast Guard Ships

While the survey was in progress, four Chinese Coast Guard vessels intruded into the adjacent waters. As they began to close in on the Shinsei Maru, Their actions forced ten Japan Coast Guard patrol boats to move in and surround the research vessel to prevent the Chinese ships from approaching it. 

They also warned the Chinese vessels to leave the area. 

Mayor Nakayama expressed appreciation to the Japan Coast Guard patrol boats and said, "We were able to gather valuable information from the research this time."

Those of us aboard the Shinsei Maru watched the fierce jockeying for position between the Chinese and Japanese vessels and for a time the scene was very tense. Once the survey ship began to depart the area in the afternoon, the Chinese vessels also started leaving the nearby waters, one after another. 

Senkaku Islands
A Japan Coast Guard patrol vessel navigates alongside a Chinese Coast Guard ship to prevent it from approaching a research vessel. January 30, off the Senkaku Islands in Ishigaki City, Okinawa Prefecture. (© Sankei by Hiroshi Kawase)

The Senkaku Islands Are Japanese Territory 

At 3:05 on the morning of January 30, passengers on Shinsei Maru suddenly heard a voice coming over the radio in the ship’s wheelhouse.

China Coast Guard Vessel 1304, this is a Japan Coast Guard patrol boat. Your vessel has entered Japan’s territorial waters. Your navigation [in these waters] is not considered harmless passage. You must leave Japan’s territorial waters immediately.


It had taken those of us aboard the research vessel chartered by Ishigaki City more than ten hours to reach this area after leaving Ishigaki Port at 5:00 PM the previous day. Uotsurishima is roughly 35 miles (56 kilometers) from Ishigaki City, which administers the Senkakus. However, the Chinese Coast Guard vessels had already entered the area and were waiting for us before we reached Japanese territorial waters adjacent to the island. 

Quickly, the Japan Coast Guard issued its warning in Japanese and Chinese. Thereafter, it did not take long for one of the China Coast Guard vessels to vehemently react. 

This is the China Coast Guard. We do not accept your claim. Diaoyudao (the Chinese name for Uotsurishima) is Chinese territory. The twelve nautical miles surrounding it are China’s territorial waters.

The Japan Coast Guard immediately retorted: 

The Senkaku Islands are Japanese territory. We do not accept your claim. 

This same back-and-forth was repeated several times after that. 

Radar Detects Outlines of Ships Near Senkaku Islands  

Shinsei Maru reached Japanese territorial waters around Uotsurishima at 6:00 AM on the morning of January 30. Since the sun had yet to rise, we were surrounded by total darkness. However, the radar of the research vessel clearly showed a Chinese ship approaching and being blocked by Japan Coast Guard patrol boats.

On the radar, we could see our ship’s position in the center of the screen. To the left, right and rear of it the outlines of three ships loomed. Those were Japan Coast Guard patrol boats. 


We could see the outlines of two other ships off to the right. Those were Chinese vessels. However, two other vessels were sticking close to them. What was happening was that Japan Coast Guard ships had created a "scrum" to prevent the Chinese vessels from approaching our research ship.

With the coming of daylight, we saw quite clearly the tight picket line set up by the Japanese ships. 

There were two vessels each to the right and left of us. Meanwhile, another was positioned to our rear. Five ships in all were sailing back and forth at regular intervals, while one or two others stood by near the island itself. 

When a Chinese ship showed up early that morning, two Japanese patrol boats sailed along on its flanks. They hemmed it in to prevent them from closing in on us.

Responding Firmly to Provocation

This was the research team's first aerial survey using a drone. Under the circumstances, their biggest concern was that the Chinese would use radio jamming or other means to knock it out of the sky. 

However, the Japanese patrol boats prevented the Chinese ships from coming near. Thanks to their effort, the research vessel was able to successfully complete the survey without encountering such problems. 

One of the members of the Tokai University research team said, "It was highly significant that the aerial survey proved successful." He was obviously looking forward to the payoff when he added, "Detailed analysis of the footage may well reveal new findings."

Nonetheless, the fact remains that China has been escalating its provocative behavior in the vicinity of the Senkakus. Chinese vessels were sighted in waters adjacent to the Senkaku Islands on a record 336 days in 2022.

Eizo Tomoyose, an Ishigaki City Council member, who was aboard the ship, says, "Responding firmly is probably the quickest way for Japan to put an end to this problem." 



(Read the article in Japanese.)

Author: Hiroshi Kawase

Our Partners