Coast Guard Cutter Munro Wraps Up Arctic Patrol After Tracking Chinese Research Ships

The U.S. Coast Guard Cutter Munro has returned to its homeport in Alameda, California, following a 112-day patrol across the Bering Sea and Arctic Ocean that included monitoring Chinese research vessels, conducting joint exercises with Canadian forces and enforcing U.S. fisheries laws.

The 418-foot national security cutter covered more than 23,000 nautical miles during the deployment, part of a broader effort to maintain a U.S. presence in the Arctic as Chinese and Russian activity draws increasing attention from Washington.

Operating under the Coast Guard Arctic District, Munro monitored three Chinese-flagged research vessels operating in and around U.S. Arctic waters under Operation Frontier Sentinel, an ongoing effort to track foreign activity near Alaska and protect U.S. sovereign rights.

The patrol included the July monitoring of the Chinese research ships Xue Long and Xue Long 2, which transited north through the U.S. Exclusive Economic Zone and over the U.S. extended continental shelf in the Bering Sea.

Foreign vessels are permitted to transit these waters under international law, but conducting marine scientific research within the U.S. EEZ or on its extended continental shelf requires prior U.S. authorization. The Coast Guard has said its monitoring operations are intended to ensure compliance with those rules and allow a rapid response to potentially unauthorized activity.

The Coast Guard did not identify the third Chinese vessel monitored during the deployment in its latest announcement.

Munro also conducted joint exercises with the Royal Canadian Navy, focusing on maritime law enforcement cooperation, maneuvering and improving awareness of vessel activity in Arctic waters.

The cutter additionally participated in Operation Tundra Merlin, which brought together U.S. and Canadian military assets to test communications, command-and-control systems and coordinated responses to potential threats in northern maritime approaches.

“The Arctic is a demanding maritime environment that can test any crew and vessel,” said Capt. Adam J. Disque, Munro‘s commanding officer.

“We also strengthened our enduring partnership with Canadian counterparts, advancing shared domain awareness and coordination across the remote region,” he added.

Beyond its security mission, Munro conducted fisheries enforcement patrols in the Bering Sea, where boarding teams inspected commercial fishing vessels for compliance with federal safety regulations and fisheries laws. The Coast Guard described the mission as protecting Alaska’s commercial fishing industry, valued at approximately $6 billion.

The deployment comes as the Coast Guard faces growing demands in the Arctic while operating with a limited number of ice-capable vessels.

In September, the service confirmed to gCaptain that the medium icebreaker Healy would not complete its planned 2026 high-latitude mission following a significant engineering casualty in July.

The breakdown left the Coast Guard relying more heavily on other assets, including the recently commissioned icebreaker Storis, national security cutters and aircraft, to maintain surveillance and patrol operations across the region.

China’s growing Arctic presence has become a particular focus. Chinese research ships have conducted increasingly visible operations in northern waters, prompting U.S. and Canadian authorities to expand monitoring of their activities.

The Coast Guard has emphasized that the presence of foreign research vessels is not itself a violation of international law, but says continued monitoring is necessary to protect U.S. interests in the region.

Commissioned in 2017, Munro is one of four Legend-class national security cutters homeported in Alameda. The ship returned to Coast Guard Island on Friday following its nearly four-month deployment.