LAKE TAHOE (AP) — The number of boats that inspectors stopped from launching at Lake Tahoe while carrying aquatic invasive species reached a record high this year, the Tahoe Regional Planning Agency said.

Inspectors intercepted 28 boats with invasive Dreissenid mussels, up from 20 in 2020 and about 10 the prior year, the Tahoe Daily Tribune reported. Dreissenid mussel species include zebra and quagga mussels.

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Despite the increase, no new invasive species have been detected in the lake, the TRPA reported on Monday.

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Traveling boats and trailers are the most common way aquatic invasive species are spread. This substantial increase in intercepted mussels stems from a large number of newly purchased boats from other states with known aquatic invasive species and a general increase in boating activity and travel, the agency said.

“With an uptick in the volume of boats, higher numbers of infested boats is expected,” said Thomas Boos, who directs the program for the Tahoe Regional Planning Agency. “The program is one of the best in the nation because we are so thorough, but it’s startling to see this shift. Boaters really need to be helping us.”

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