TOKYO -- Something funny is going on in the waters around the Senkaku Islands, and it's making Japan nervous.
There has been a precipitous decline in the presence of Chinese government surveillance vessels around the group of islets in the East China sea, which are controlled by Japan but claimed by China. At the same time, the number of Chinese fishing vessels operating in the area has surged, a development some see Beijing's new approach in pursuing its territorial claims.
During the 10th Tokyo-Beijing Forum, held Sept. 28-29 in the Japanese capital, a Chinese military official surprised participants by proposing a long list of steps to prevent a security crisis.
His 25 proposals included the establishment of hotlines between the navies and air forces of the two countries and joint efforts to establish common rules concerning maritime operations. He called for "serious working-level discussions" over these proposals.
There are also signs of a thaw in the frosty bilateral relations. Beijing has informed Tokyo of its intention to reopen suspended talks to build an emergency maritime communications system.
Moreover, the cases of intrusions by Chinese surveillance vessels into Japanese territorial waters around the islands have also decreased. The average monthly number of Chinese ships entering the area during the first nine months of this year was 7.1, less than half of the 17.6 for the same period last year.
As Chinese President Xi Jinping has managed to consolidate his power at home, observers say, he is turning his attention to soothing tensions with Japan.
The situation unfolding around the disputed islands, however, seems to contradict this view.
A new tactic?
From January to September, the Japan Coast Guard told Chinese fishing boats operating within Japanese waters around the Senkaku Islands to leave on 208 occasions, a 2.4-fold jump from last year and 26 times larger than the figure for 2011.
So far, Chinese fishing boats have put up little resistance when warned by the coast guard to leave, but a Japanese security official says the situation could lead to a maritime collision like the one that occurred in autumn 2010, exacerbating bilateral tensions.
Several theories about this surge in fishing activity are circulating within the Japanese government.
One says it is simply a natural consequence of the expansion of China's fishing operations in general. But according to a Japanese fisheries industry source, the number of Chinese fishing boats operating in southern region of the East China Sea, where the Senkaku Islands are located, has held steady at around 1,000 in recent years.
This indicates there is no natural reason for the surge in the number of Chinese ships operating around the islands and provides support to another theory: Chinese authorities are simply looking the other way.
Beijing had been trying, to some extent, to prevent Chinese fishing vessels from coming close to the Senkakus. But some Japanese policymakers believe it started easing such efforts after the Japanese government purchased the islands from a private landowner in September 2012.
China likely recognizes that deploying more patrol boats to the area would only provoke Japan and its ally, the U.S., and is thus seeking to erode Japan's effective control over the islands by letting fishing boats operate near them.
China has been making only lukewarm efforts to keep its fishing boats from approaching the Senkakus. Since last year through September, there have been only around 10 cases in which a Chinese surveillance vessel stopped and inspected a Chinese fishing boat, according to a Japanese government official.
On the other hand, Tokyo would not be happy if China started making serious efforts to crack down on operations by Chinese boats, as that would give Beijing a precedent of legal administration over the area, a senior official at the Foreign Ministry said.
What is most worrisome for Japan is the possibility that Chinese maritime militia forces disguised as fishermen may enter areas around the islands.
There has been no confirmed case of an armed Chinese fishing ship entering waters around the islands, according to the Japan Coast Guard, but it has been reported that maritime militias trained by the Chinese military were mobilized for territorial disputes in the South China Sea.