Flighted Spongy Moth Complex 2025
Due to the Flighted Spongy Moth’s destructive nature, particularly in countries where the pest is not indigenous, the following countries have specific procedures in place to prevent FSMC from entering their fragile eco system:
- Argentina
- Australia
- Canada
- Chile
- New Zealand
- United States
Details can be found below.
Introduction
The Flighted Spongy Moth Complex (“FSMC”, including Lymantria dispar asiatica, Lymantria dispar japonica, Lymantria albescens, Lymantria umbrosa, Lymantria postalba) is a highly destructive forest pest that feeds on both deciduous and coniferous trees.
The voracious appetite of FSMC larvae (caterpillars) coupled with the ability of the female moth to travel significant distances (as much as 20 nautical miles) can cause widespread defoliation leaving trees weakened and susceptible to disease and other pests.
FSMC is found primarily in Asia or Russia with a high risk of FSMC egg infestation of vessels calling at ports in Korea, Northern China (north of Shanghai; ports north of latitude 31˚15’N), and in particular the Russian Far East and Japan during the flight season of the female moth.
It is important to highlight that certain countries still employ the former term "Asian Gypsy Moth" (AGM) in their official communications. Nevertheless, these authorities are undergoing a transition towards adopting FSMC.
FSMC/AGM Flight Season
The main concern to countries attempting to prevent the introduction of the FSMC are vessels that have called at ports in an FSMC High Risk Area during the “flight season”.
The specific timing of the “flight season” differs from country to country:
Argentina
Asian Gypsy Moth Endemic Area (For ports located between 60°N and 20°N) | Female Flight Season |
Russian Far East (Petropavlovsk-Kamchatskiy; Vanino; Nevelsk; Kholmsk; Korsakov; Kozmino; Slavyanka; Posiet; Zarubino; Vostochny; Nakhodka; Vladivostok.) | 15 June to 15 October |
China All ports | 1 June to 30 September |
Korea (Ulsan, Pohang, Mokpo, Yeosu, Gunsan, Gwangyang, Hadong, Samcheonpo, Boryeong, Daesan, Taean, Donghae-Mukho, Okgye, Hosan, Busan, Jinhae, Masan, Tongyeong, Jangseongpo, Okpo, Gohyeon, Incheon, Pyeongtaek- Dangjin) | 1 June to 30 September |
Northern Japan (Hokkaido, Aomori, Iwate, Miyagi and Fukushima Prefectures) | 15 June to 15 October |
Western Japan (Akita, Yamagata, Niigata, Toyama and Ishikawa Prefectures) | 1 June to 30 September |
Eastern Japan (Fukui, Ibaraki, Chiba, Tokyo, Kanagawa, Shizuoka, Aichi and Mie Prefectures) | 1 June to 30 September |
Southern Japan (Wakayama, Osaka, Kyoto, Hyogo, Tottori, Shimane, Okayama, Hiroshima, Yamaguchi, Kagawa, Tokushima, Ehime, Kochi, Fukuoka, Oita, Saga, Nagasaki, Miyazaki, Kumamoto and Kagoshima Prefectures) | 15 May to 31 August |
Far South Japan (Okinawa) | 25 May to 30 June |
Australia
Asian Gypsy Moth Endemic Area | Female Flight Season |
Russian Far East (Ports between 40°N and 60°N and west of 147 °E) | 1 July to 30 September |
Chile
Asian Gypsy Moth Endemic Area (For ports located between 60°N and 20°N) | Female Flight Season |
Russian Far East | 15 June to 15 October |
China (Ports north of 31°15’N) | 1 June to 30 September |
North Korea | 1 June to 30 September |
Republic of Korea | 1 June to 30 September |
Northern Japan (Hokkaido, Aomori, Iwate, Miyagi, Yamagata, Akita and Fukushima Prefectures) | 15 June to 15 October |
Western Japan (Niigata, Toyama and Ishikawa Prefectures) | 1 June to 30 September |
Eastern Japan (Fukui, Ibaraki, Chiba, Tokyo, Kanagawa, Shizuoka, Aichi and Mie Prefectures) | 1 June to 30 September |
Southern Japan (Wakayama, Osaka, Kyoto, Hyogo, Tottori, Shimane, Okayama, Hiroshima, Yamaguchi, Kagawa, Tokushima, Ehime, Kochi, Fukuoka, Oita, Saga, Nagasaki, Miyazaki, Kumamoto and Kagoshima Prefectures) | 15 May to 31 August |
Far South Japan (Okinawa) | 25 May to 30 June |
New Zealand
Asian Gypsy Moth Endemic Area | Female Flight Season |
Russian Far East (South of 60°N and west of 147°, excluding ports in the Kamchatka Peninsula) | 15 June to 15 October |
China (North of 31°15’N) | 1 June to 30 September |
Republic of Korea (all ports) | 1 June to 30 September |
Northern Japan (Hokkaido, Aomori, Iwate, Miyagi and Fukushima, Akita, Yamagata Prefectures) | 15 June to 15 October |
Central Japan (Niigata, Toyama, Ishikawa, Fukui, Ibaraki, Chiba, Tokyo, Kanagawa, Shizuoka, Aichi, Mie Prefectures) | 1 June to September 30 |
Southern Japan (Wakayama, Osaka, Kyoto, Hyogo, Tottori, Shimane, Okayama, Hiroshima, Yamaguchi, Kagawa, Tokushima, Ehime, Kochi, Fukuoka, Oita, Saga, Nagasaki, Miyazaki, Kumamoto and Kagoshima Prefectures) | 15 May to 31 August |
Far South Japan (Okinawa) | 25 May to 30 June |
United States & Canada
The specified risk period is for vessels entering ports in high-risk areas during 2025, the bold sections highlighted below are the new risk periods.
Asian Gypsy Moth Endemic Area | Female Flight Season |
Russian Far East (Kozmino, Nakhodka, Ol’ga, Plastun, Pos’yet, Russkiy Island, Slavyanka, Vanino, Vladivostok, Vostochny and Zarubino) | 15 June to 15 October |
Northern China (including all ports on or North of 31°15’N) | 1 June to 30 September |
Republic of Korea (all ports) | 1 June to 30 September |
Northern Japan (Hokkaido, Aomori, Iwate, Miyagi, Yamagata, Akita and Fukushima Prefectures) | 15 June to 15 October |
Central Japan (Niigata, Toyama and Ishikawa, Fukui, Ibaraki, Chiba, Tokyo, Kanagawa, Shizuoka, Aichi and Mie Prefectures) | 1 June to 30 September |
Southern Japan (Wakayama, Osaka, Kyoto, Hyogo, Tottori, Shimane, Okayama, Hiroshima, Yamaguchi, Kagawa, Tokushima, Ehime, Kochi, Fukuoka, Oita, Saga, Nagasaki, Miyazaki, Kumamoto and Kagoshima Prefectures) | 15 May to 31 August |
Far South Japan (Okinawa) | 25 May to 30 June |
Flighted Spongy Moth Complex Characteristics

Male FSMCs are greyish brown with a wingspan of 30 to 40 mm. Females are whitish / pale yellow in colour with prominent black marks on the wings and are larger than the male with a wingspan of 40 to 70 mm.
It is unlikely that live FSMCs will be encountered by vessels in transit. It is more likely that egg masses will be found.
Female FSMCs are active flyers and are attracted to bright lights, therefore FSMC eggs may be found in the vicinity of exterior lights and floodlights on vessels. If powerful shore lights are directed towards the vessel, FSMC eggs may be found all over the ship and its cargo. Where safe and practicable to do so, external lights on vessels should be switched off.
FSMC eggs are velvety in texture and range in colour from light tan to dark brown. A typical egg mass will contain between 500 and 1000 eggs and measure approximately 20 mm by 40 mm. The eggs are particularly hardy and resistant to changes of temperature and moisture. They are normally deposited in sheltered locations, for example, under canvas covers, around light fixtures and underneath framing arrangements such as hatch coamings and the underside of bridge wings. Egg masses have also been found on mooring lines, on the outside of shipping containers and on vehicles, for example in wheel arches

The larvae normally hatch in early spring and this is therefore considered the high risk period in countries that wish to stop this species becoming established. Consequently, vessels that call in Asia or Russia during the flight season, and then subsequently arrive in port during the hatching period, are of particular concern.
The peak period for egg hatching is in the morning; the dispersing larvae move towards vertical structures, climb rapidly to a high point and are then widely dispersed on silken strands by the wind until they find suitable host trees to feed on, a process known as “Ballooning”.
Inspections
The inspection of vessels for the presence of egg masses, their removal and disposal are the principal tools in preventing FSMC becoming established in new regions.
Some destination countries require vessels that have called in high risk countries during the flight season to be inspected and certified free of FSMC by a nominated authority immediately prior to departure.
If no signs of FSMC infestation are found, the nominated authority will issue the vessel with certification stating that it is free of FSMCs; depending on the issuing authority the certificate may be a “Certificate of Inspection of Freedom from the Flighted Spongy Moth Complex” or a “Phytosanitary Certificate”.
If multiple ports in the same country or a number of ports in different countries within the high risk area are visited during the flight seasons, the official inspection should be undertaken immediately prior to departure from the last port in the high risk area during the applicable flight season.
Regardless of any requirement for an official inspection, to mitigate the risk of infestation when calling at ports in the high-risk area during the FSMC flight season, vessels are advised to:
- Carry out a thorough visual inspection of the accommodation superstructure, decks, deck machinery, holds, cargo and cargo gear immediately prior to departure. Binoculars can be used to inspect difficult to reach areas of the vessel’s superstructure, such as the underside of bridge wings. Similarly, a small mirror attached to a stick may be used to inspect areas that are difficult to see, for example, behind pipework next to the hatch coaming.
- Carry out another thorough visual inspection while on passage to the destination port.
- Scrape off any egg masses that are found. Do not paint over them as this will not kill them. Do not remove them using high pressure water guns as some eggs may be washed over the side and immersion in saltwater does not kill them; there have been cases of FSMC eggs floating to shore and continuing to develop and hatch.
- Prior to arrival destroy any egg masses that have been scraped off. Eggs may be destroyed by placing them in alcohol, boiling them in water, freezing them or by incineration.
- Record details of all visual inspections and the removal and disposal of FSMC eggs in the vessel’s deck logbook.
Country Specific Requirements
When proceeding to any of the following countries after having visited the high-risk area during the female flight season, the specific requirements of the destination should be followed:
Argentina
The Argentinian National Service for Health and Agrifood Quality (SENASA) have finalised approval and issuance of a resolution that established national FSMC/AGM control measures.
SENASA has adjusted its female "flight season" to align more closely with the requirements of the USA and Canada. Further details can be found in Resolution No 533-2022 issues by SENASA. Specific requirements and necessary documentation for entering Argentina during the flight season are outlined in Circular 35/2020. The Club’s regional correspondents recommend that in addition to fulfilling Argentina's requirements, crew members should also contact the ship's agents in Argentina for each specific case.
Australia
The latest Department of Agriculture and Water Resources requirements are detailed in the below Industry Advice Notice:
277-2022 – Commencement of Asian Gypsy Moth Vessel Assessment and Inspection Arrangements. (Reviewed on 22nd December 2022)
All relevant vessels will be sent an FSMC questionnaire through the Maritime Arrivals Reporting System (MARS),as part of their Pre-Arrival Reporting (PAR) process.
Chile
The Requirements are set out in Resolution 4412/2013 – Phytosanitary Requirements for Vessels Arriving from Areas with Flighted Spongy Moth Complex (still referred to under previous name Asian Gypsy Moth “AGM”) Presence, as amended by Resolution 8394/2021– Modified Phytosanitary Requirements for Vessels Arriving from Areas with Flighted Spongy Moth Complex Presence. Further information can be found on 2 SAG posters.
It should be noted that the 2021 amendment makes the flight season more in line with other countries stated flight season.
New Zealand
They changed their policy in 2023 regarding the regulated areas in order to be more in line with the requirements for the USA and Canada, further details can be found on the Spongy Moth – what you need to know.
FSMC requirements are set out in part 3 of the Craft Risk Management Standard (CRMS) - Vessels. Further details can be found in the Arrival process steps, and on the following Biosecurity New Zealand webpage, which includes a link to a list of approved FSMC inspection bodies: Hitchhiker pests.
The Ministry for Primary Industries has also published a Fact Sheet to assist Owners and Operators of Commercial Vessels.
USA and Canada
FSMC requirements are set out in the Flighted Spongy Moth Complex (FSMC) 2025 jointly by the Canadian Food Inspection Agency (CFIA) and the United States Department of Agriculture (USDA). Specific country requirements can be seen in full here (for Canada) and here (for USA).
Inspectors have found that in North American ports there were a high number of FSMC egg masses recorded in previous years. Therefore, for 2025, extra vigilance should be taken in conducting self-inspections and receiving required certification in FSMC regulated areas. Scheduling inspection and certification services well in advance, along with providing a two-year port of call history at the time of the request is what is required of the vessel.
FSMC Charter Party Clause
When negotiating charter parties, Members may wish to include the following clause if the vessel could be required to call at ports in the high-risk region during the flight period:
“Should Charterers order the vessel to a port, place, country or area infested by Flighted Spongy Moth Complex ("FSMC") or where there is risk of exposure to infestation by FSMC as reasonably determined by the Master, Charterers shall take all reasonable steps at their time and expense to ensure that the vessel does not become infested. Without prejudice to this
obligation, Charterers shall, at their time and expense, arrange for the appropriate certificate stating that the vessel is free from infestation by FSMC, its larvae or eggs to be issued by an appropriate and recognised authority to the satisfaction of the Master just prior to departure from the last port of call within the high risk area during the flight season. Notwithstanding the issuing of such a certificate, Charterers will be responsible for any consequences whatsoever, including but not limited to time, costs and third party liabilities to cargo interests etc., howsoever arising, and the vessel to remain on hire/laytime to count (as applicable) should an infestation of FSMC be found or suspected and/or should delays or costs be incurred due to charterers having ordered the vessel to call at a port, place, country or area where the presence of FSMC is known or suspected.”
Additional Information
Additional information on the FSMC/AGM can be found in the: Gypsy Moth Inspectional Pocket Guide.
Members requiring further guidance or assistance should contact the Loss Prevention department.