Operators of vessels trading in FSMC high-risk regions of key preventive measures, offering practical tips to help crews inspect, remove, and properly dispose of egg masses to reduce infestation risks.

The Flighted Spongy Moth Complex (FSMC), which includes Lymantria dispar asiatica, Lymantria dispar japonica, Lymantria albescens, Lymantria umbrosa, and Lymantria postalba, is a highly destructive forest pest found primarily in Asia and Russia. Its larvae feed aggressively on both deciduous and coniferous trees, and the female moth’s ability to fly up to 20 nautical miles enables rapid spread, leading to severe defoliation and weakening of forests.

Vessels calling at ports in high-risk regions such as Korea, Northern China (north of latitude 31˚15’N), the Russian Far East, and Japan are especially susceptible to FSMC egg infestations during the female moth’s flight season. While some countries still use the older term “Asian Gypsy Moth” (AGM), there is a growing shift toward adopting the more accurate term FSMC in official documentation.

Vessel inspection for infestations 

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.

5 tips for compliance 

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:

  1. 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.
  2. Carry out another thorough visual inspection while on passage to the destination port.
  3. 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.
  4. 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.
  5. Record details of all visual inspections and the removal and disposal of FSMC eggs in the vessel’s deck logbook.