Almost two months after invasive zebra mussels were discovered in imported “moss balls” (actually algae) in a Seattle PetCo store, federal and state agencies are still trying to track the Trojan moss balls and keep the mussels out of vulnerable water bodies, including California’s. So far, contaminated moss balls have been found in 46 states (Virginia, Delaware, Rhode Island, and Hawaii are the exceptions) and most of Canada’s provinces. The US Fish & Wildlife Service has issued detailed guidance for getting rid of the moss balls, summarized as “Destroy, Dispose, Drain,” and the Pet Industry Joint Advisory Council has followed suit.  The Animal and Plant Health Inspection Service (APHIS), Customs and Border Protection, and the US Geological Survey are also involved. Authorities have identified multiple moss ball importers in seven states, some of them in California.  Some importers get their stock from Ukraine, a known source of both moss and mussels.  Meanwhile, another worrisome invader, the Mediterranean marine alga Caulerpa prolifera, recently turned up in Newport Bay, reinforcing the need for vigilant early detection work. A related species, C. taxifolia, appeared in Southern California earlier, but a multi-agency effort eradicated it in 2006.

How to Dispose of Mussels and Moss Balls, USFWS

Caulerpa Found in Newport Bay, CDFW

Estuary News Stories

Red Alert on Moss Balls, March 2021 Estuary News

Kitchen Sink Update Every Last Invader, September 2018, Estuary News

Table Set for Apple Snails, December 2017, Estuary News

Pearls in the ocean of information that our reporters didn’t want you to miss

Invasions

Almost two months after invasive zebra mussels were discovered in imported “moss balls” (actually algae) in a Seattle PetCo store, federal and state agencies are still trying to track the Trojan moss balls and keep the mussels out of vulnerable water bodies, including California’s. So far, contaminated moss balls have been found in 46 states (Virginia, Delaware, Rhode Island, and Hawaii are the exceptions) and most of Canada’s provinces. The US Fish & Wildlife Service has issued detailed guidance for getting rid of the moss balls, summarized as “Destroy, Dispose, Drain,” and the Pet Industry Joint Advisory Council has followed suit.  The Animal and Plant Health Inspection Service (APHIS), Customs and Border Protection, and the US Geological Survey are also involved. Authorities have identified multiple moss ball importers in seven states, some of them in California.  Some importers get their stock from Ukraine, a known source of both moss and mussels.  Meanwhile, another worrisome invader, the Mediterranean marine alga Caulerpa prolifera, recently turned up in Newport Bay, reinforcing the need for vigilant early detection work. A related species, C. taxifolia, appeared in Southern California earlier, but a multi-agency effort eradicated it in 2006.

How to Dispose of Mussels and Moss Balls, USFWS

Caulerpa Found in Newport Bay, CDFW

Estuary News Stories

Red Alert on Moss Balls, March 2021 Estuary News

Kitchen Sink Update Every Last Invader, September 2018, Estuary News

Table Set for Apple Snails, December 2017, Estuary News

Zebra mussel in moss ball courtesy Oregon Fish & Wildlife.


Senior Editor: Cariad Hayes Thronson

Social Media Editor: Sierra Garcia

Ideas for Pearls: Contact [email protected]com

About the author

Joe Eaton writes about endangered and invasive species, climate and ecosystem science, environmental history, and water issues for ESTUARY. He is also "a semi-obsessive birder" whose pursuit of rarities has taken him to many of California's shores, wetlands, and sewage plants.

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