Government conservation officials announced Monday they'd responded "swiftly" and "decisively" to a threat of an invasive species at Shuswap Lake this month, removing a U.S. boat some quagga mussels rode in on.

Experts removed the vessel July 3, after the fingernail-sized mussels were found on a powerboat transported from Arizona - hoping to prevent them from becoming established in the lake.

Though sample mussels turned out to be dead, some might have been alive when the boat docked in Shuswap Lake, so experts are analyzing water samples from the boat for mussel larvae. Divers will also inspect the marina's moorage area, piers and lakebed.

Gail Wallin of the Invasive Species Council of B.C. confirmed the boat was also screened for - and found free of - zebra mussels, another invasive freshwater species commonly found with quagga mussels and equally tough to eradicate.

The government warned the introduction and establishment of zebra or quagga mussels into B.C. would change the biodiversity of its water systems, threaten native species and fisheries, and increase maintenance costs related to the operation of hydroelectric, industrial, agricultural and recreational facilities.