RENO, Nev. (AP) - A 32-foot cabin cruiser was quarantined at Lake Tahoe after a harbor master spotted invasive mussels encrusted on its stern as it was about to be hoisted into the water.

Wildlife and environmental experts describe the incident as a close call.

Experts confirmed the mollusks were quagga mussels, which apparently attached to the vessel while in Lake Mead in late July.

Officials say the boat will be checked next week to be sure it's clean before being released to its owner.

Quagga mussels, previously found only in the Midwest and Northeast, were first discovered in Lake Mead in early 2007 and have since spread to other parts of Nevada, Arizona and Southern California.

Officials say the mussels could cause widespread ecological problems if they were to become established in Lake Tahoe.

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