It’s still Flighted Spongy Moth Complex (formerly known as Asian Gypsy Moth) season on the US west coast, so if your ship has recently sailed from a port in East Asia and is on it’s way to our part of the world, then you should have a FSMC certificate showing that it was inspected for, and found free from, any infestation.
If your vessel has a port call at any of the locations discussed below, within the specified dates, then your ship must arranged for a proper inspection and obtain a FSMC certificate before departing that port. However, if you have not done so and your vessel is already on its way to the US west coast region then let NASA know and we will let you know how to proceed.
Russia (Far East)
Ports: Nakhodka, Ol'ga, Plastun, Pos'yet, Russkiy Island, Slavyanka, Vanino, Vladivostok, Vostochny, Zarubino, Kozmino.
Risk Period: June 15 to October 15
People's Republic of China
Ports: All ports in northern China located on or north of 31°15' N. (This excludes ports like Zhoushan, which is further south).
Risk Period: June 1 to September 30
Republic of Korea
Ports: All ports.
Risk Period: June 1 to September 30
Japan
Northern Japan: (Hokkaido, Aomori, Iwate, Miyagi, Yamagata, Akita, Fukushima Prefectures)
Risk Period: June 15 to October 15
Central Japan: (Aichi, Chiba, Fukui, Ibaraki, Ishikawa, Kanagawa, Mie, Niigata, Shizuoka, Tokyo, Toyama Prefectures)
Risk Period: June 1 to September 30
Southern Japan: (Ehime, Fukuoka, Hiroshima, Hyogo, Kagawa, Kagoshima, Kochi, Kumamoto, Kyoto, Miyazaki, Nagasaki, Oita, Okayama, Osaka, Saga, Shimane, Tokushima, Tottori, Wakayama, Yamaguchi Prefectures)
Risk Period: May 15 to August 31
Far Southern Japan: (Okinawa Prefecture)
Risk Period: May 25 to June 30
DRAFT 2
Don't Let an Uninvited Passenger Ruin Your Voyage: The 2026 Flighted Spongy Moth Complex Rules Are Here
Ah, summer at sea. The ocean breeze, the open water, and... a massive swarm of extremely invasive, tree-devouring hitchhikers?
If you haven’t heard, the insect formerly known as the Asian Gypsy Moth has undergone a bit of a corporate rebranding. It is now officially called the Flighted Spongy Moth Complex (FSMC). While the new name might sound like a high-end luxury spa or a sci-fi villain lair, these little critters are a major headache for maritime operations.
Female FSMC moths are strong fliers and are utterly obsessed with the bright lights of your vessels. They love nothing more than flying aboard at night and laying hard-to-spot egg masses in the cozy, sheltered corners of your ship.
Because these pests can completely decimate forestry and fruit industries, agricultural authorities worldwide (especially in the US, Canada, Australia, New Zealand, Chile, and Argentina) are on high alert. If your ship calls on certain high-risk regions during their 2026 "flight season," you must obtain a certified FSMC-free certificate before departing. If you don't, prepare for hefty delays, aggressive inspections, or being ordered straight out of port.
To keep your voyage smooth and moth-free, here is the official breakdown of the high-risk zones, ports, and specific dates for the 2026 season:
The 2026 FSMC High-Risk Areas and Dates
Russian Far East
High-Risk Window: June 15 to October 15, 2026
Regulated Ports: Nakhodka, Ol'ga, Plastun, Pos'yet, Russkiy Island, Slavyanka, Vanino, Vladivostok, Vostochny, Zarubino, and Kozmino.
People's Republic of China
High-Risk Window: June 1 to September 30, 2026
Regulated Ports: All ports in northern China, specifically any port located on or north of 31°15′ N.
Republic of Korea (South Korea)
High-Risk Window: June 1 to September 30, 2026
Regulated Ports: All ports nationwide.
Northern Japan
High-Risk Window: June 15 to October 15, 2026
Regulated Prefectures: Akita, Aomori, Fukushima, Hokkaido, Iwate, Miyagi, and Yamagata.
Central Japan
High-Risk Window: June 1 to September 30, 2026
Regulated Prefectures: Aichi, Chiba, Fukui, Ibaraki, Ishikawa, Kanagawa, Mie, Niigata, Shizuoka, Tokyo, and Toyama.
Southern Japan
High-Risk Window: May 15 to August 31, 2026
Regulated Prefectures: Ehime, Fukuoka, Hiroshima, Hyogo, Kagawa, Kagoshima, Kochi, Kumamoto, Kyoto, Miyazaki, Nagasaki, Oita, Okayama, Osaka, Saga, Shimane, Tokushima, Tottori, Wakayama, and Yamaguchi.
Far Southern Japan
High-Risk Window: May 25 to June 30, 2026
Regulated Prefecture: Okinawa.
What Shipowners Need to Do
Data indicates that FSMC populations are hitting outbreak levels in 2026, meaning destination ports will be examining your paperwork and vessel with a magnifying glass.
Get the Certificate: If you dock in any of the areas above during the listed dates, you must get an official pre-departure inspection and a certificate stating your vessel is free of FSMC life stages.
Dim the Lights: While in these ports, turn off unnecessary exterior lights to avoid throwing an open-invite party for the local moth population.
Scrape and Destroy: Conduct thorough self-inspections. Check around accommodation blocks, look under coamings, and inspect cargo gear. If you see fuzzy, yellowish-brown egg masses, scrape them off and destroy them properly before arriving at your next destination.
Safe sailing, keep your eyes peeled, and don't let a moth hold up your ship!