By Chen Mei-hua | 2025-07-16

China's deployment of oceanographic research vessels is an example of gray zone tactics playbook -- while they appear to conduct scientific missions, in reality they often conduct military intelligence collection and help achieve broader maritime strategic goals.

In June, the Chinese research vessel Kexue returned after a two-month scientific survey in the western Pacific, according to an announcement by Qingdao Customs, the customs authority for the city of Qingdao.

So far this year, the authority said it has processed entry and exit procedures for five research vessels a total of eight times, adding that it has "effectively supported China's oceanographic research efforts in deep waters."

However, vessels such as the Kexue often masquerade as scientific research ships while actually conducting sensitive missions, Jun Kajee, an analyst at the maritime transparency initiative SeaLight, wrote on June 3.

These missions include seabed mapping and monitoring foreign military and commercial activity, which in turn supports China's submarine operations, marine resource exploitation and sovereignty claims.

Drawing on ship-tracking data from Starboard Maritime Intelligence, Kajee documented several suspicious operations.

In 2023, for instance, the Xiang Yang Hong 10 sailed a path appearing to "trace the Chinese character "中" ("China")" in contested Vietnamese waters.

This may have served as a symbolic "psychological signaling or territorial assertion," Kajee wrote.

That same year, the Haiyang Dizhi 8 conducted a prolonged survey in Malaysia's Exclusive Economic Zone, and Japan's coast guard detected the Xiang Yang Hong 18 operating suspiciously near the disputed Senkaku Islands.

Earlier this year, the Dong Fang Hong 3 surveyed the Indian Ocean seabed, while the Tan Suo Yi Hao operated for extended periods off New Zealand and Australia.

Chinese coast guard and maritime militia vessels frequently accompany these survey missions to intimidate regional actors, said Kajee.

"Confronting a nominally civilian vessel risks escalation and international criticism," he said, adding that "these operations are part of a broader 'salami-slicing' strategy, advancing China's interests step by step below the threshold likely to trigger open conflict."

'Hiding the blade'

Many Chinese research vessels have high-precision underwater acoustic positioning systems, said Zhou Feng, a professor from Harbin Engineering University, as quoted by a June report in Guangming Daily.

These systems can pinpoint targets within a one-meter margin, essentially serving as the "eyes" for deep-sea submersibles, he said.

These vessels often install large sonar arrays designed to map underwater terrain in detail, Taiwanese military analyst Wu Ming-chieh told Focus.

This information helps Chinese submarines navigate deep waters and identify favorable ambush zones, potentially including the patrol routes of US submarines.

He described these efforts as a form of "battlefield preparation" across the Indo-Pacific, calling them a gray zone tool of underwater encroachment.

Chinese gray zone tactics around Taiwan are "quasi-aggressive actions," Huang Tsung-ting, an associate research fellow at Taiwan's Institute for National Defense and Security Research, told Focus.

While military drills represent China "flashing the sword," these research vessels "quietly loitering" near Taiwan's waters are "hiding the blade," he said.

These ships often sail close to Taiwan's 24-nautical-mile contiguous zone under the pretext of scientific work, but in reality, they are gathering sensitive hydrological and military-use data, according to Huang.

A July New York Times investigation reported that in 2024, Chinese ships like the Xiang Yang Hong 6 repeatedly surveyed the seafloor off Taiwan's east coast.

They followed slow, parallel, and grid-like paths, ideal for sonar-based bathymetric mapping. Some vessels came close to Taiwan's 12-nautical-mile territorial boundary.

"The big takeaway for me is: It appears that China is trying to collect bathymetric data on that part of the ocean without appearing like it is conducting a bathymetric survey," said Ryan D. Martinson, an assistant professor at the US Naval War College, speaking in a personal capacity in the report.

Reducing uncertainty

Beyond survey ships, emergency cable-laying vessels suspected of cutting undersea telecom cables in the Taiwan Strait have raised alarms.

Describing such actions merely as "gray zone" risks understating their severity, said Huang.

While other nations have long used oceanographic surveys for military purposes, China differs in fusing intelligence collection with coercive assertions of sovereignty, National University of Singapore political scientist Ian Chong told Focus.

Escorted by the Chinese militia and coast guard, ships are carrying out more and more of these missions across Indo-Pacific waters.

"The essence of gray zone tactics lies in ambiguity, making it hard for the other side to respond clearly. One counterstrategy is to increase transparency and reduce uncertainty," Chong said.

He pointed to the Philippines' success in reducing Beijing's direct provocations by publicly documenting its maritime behavior.

Still, he cautioned, any sustained response will require patience and resilience against China's long-term pressure -- similar to the Cold War's drawn-out tensions and gradual balancing process.