Lake Tahoe faces the threat of invasive species

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Lake Tahoe faces the threat of invasive species


Photo of Quagga mussel from Wikimedia Commons.

Fourth of July is just around the corner and that means it's prime boating season at Lake Tahoe. But with that comes the threat of invasive species. And wildlife officials are hoping no unwelcome creatures find their way into the lake this year.

On the second day of the season, Zak Lance intercepted a boat at his inspection station that had full grown Quagga mussels caked to the back of it. They're the kinds of mussels that could devastate the lake's ecosystem.

"We collect those as evidence. The state comes out and inspects the boat. We end up quarantining it if necessary," Lance says.

Not all inspections at the station here at Northstar are that dramatic. A long black motor boat from Modesto doesn't appear to have the same issue. But like every boat that enters the lake, it still needs to be decontaminated. Right now, Lance and his crew are scrambling around the boat with hoses and vacuums.

"So basically we flush all the raw water systems on the boat with hot water," Lance says. 140 degree water will kill anything in about 10 seconds."

Quagga mussels are one of the biggest threats to LakeTahoe. So far there's no evidence that any have hitched a ride. But Asian clams and some warm water fish have made it into the lake. With Quagga mussels, the tricky thing is that even a puddle of water in the hull of a boat could be harboring them.

"When they're in their smallest form they're microscopic and we're not going to get out a microscope on every boat."

Lance says it's been a busy start to the season. Just earlier in the day there was a line of boats all the way to the end of the parking lot. He suspects business will pick up even more into July because of the drought. So many other lakes in California, like Folsom, don't have enough water and that could drive more business to Tahoe.

Nicole Cartwright, who's with the Tahoe Resource Conservation District, says it's hard to know exactly how an invasive species could affect the lake, but it's most certainly not beneficial.

"Quagga mussels are filter feeders and so they take out a lot of the lower level of the food chain and so that's a lot of the micro-organisms that are feeding our smaller fish," Cartwright says. "And so we could see a pretty big affect in our native fish populations."

A mussel can live anywhere from 5 to 30 days out of water, and up to 60 days in a moist environment. And for that reason any boat that enters the lake must be mussel free.