Washington Finds Invasive Zebra Mussels In Retail Moss Balls

Have an aquarium? If so, Washington wildlife officials want you to check your stock for a certain brand of moss balls that may have come with an unwelcome guest.

According to the Washington Department of Fish and Wildlife, investigators this week became aware of invasive zebra mussels that hitched a ride with a shipment of "Betta Buddy" Marimo moss balls. Enforcement officers removed 56 of the moss balls from a Seattle Petco and found at least 12 zebra mussels among them, officials said.

The unwelcome discovery led other states to investigate and confirmed the presence of zebra mussels at other retailers selling the Marimo brand, including PetSmart. WDFW said both Petco and PetSmart moved quickly to pull the product from physical and online stores nationwide.

Now, the challenge is tracking down those that may have already been sold.

"We're working closely with regulatory authorities, our vendor partners, and our own veterinary staff on appropriate next steps, including proper handling and disposal of any affected products and proactively contacting our customers to provide information and resources on how to responsibly collect and dispose of them at home if necessary," said Whitney Miller, head of veterinary medicine at Petco.

According to the WDFW, zebra and quagga mussels are freshwater mollusks that make their home on lakes and rivers. However, their introduction can have significant environmental and economic impacts.

"These species could cost taxpayers hundreds of millions of dollars a year and close down access to state waters for recreation and commercial opportunities," the Washington Invasive Species Council writes. "They clog water intake pipes and filters, reducing water pumping capabilities for power and water treatment plants. Once established, these mussels will change ecosystems and food sources critical to native mussels and species such as salmon and trout."

Here's how to recognize a zebra mussel:

• Adults range from 1/8 to 2 inches in length.
• Mostly white or cream with jagged brown or black stripes across the shell. Shell is D-shaped.
• Byssal threads (or ropes) are on the hinge edge of its shell. These threads are unique to zebra and quagga mussels and are not found on native mussels.

Anyone who thinks their aquarium may be contaminated with the invasive mussels can file a report via the state's online system.

The state also shared two methods for properly destroy contaminated moss balls:

1. Remove the moss ball(s) and place in a plastic bag. Put the bag in the freezer and leave for at least 24 hours. After that, the moss ball(s) can be disposed of in the trash.
2. Place moss ball(s) in boiling water for at least one full minute. After that, the moss ball(s) can be disposed of in the trash.

Officials said an investigation into the mussels' origin is underway, and wholesale distributors in California and Florida halted shipments of the moss balls.

Learn more about the discovery and the threat of zebra mussels on the Washington Invasive Species Council's website.