Emerald Bay at Lake Tahoe is seen here.

(Brant Allen/UC Davis TERC)

At a Glance

The iconic blue waters of the lake continue to be threatened by global warming.The invasive shrimp eat zooplankton that helps keep the water clear.Billions of the shrimp live in the lake.

Eliminating tiny, invasive shrimp from Lake Tahoe could improve clarity in the largest alpine lake in North America, a new report says.

The iconic blue waters of the lake continue to be threatened by warmer temperatures brought on by global warming, according to the annual released Thursday by the University California Davis' Tahoe Environmental Research Center.

But, the report says, a new project that seeks to remove Mysis shrimp, a tiny invasive species, from the lake could help mitigate some of that damage.

(MORE: L.A. Utility Department Accused of Destroying Endangered Plants During Wildfire Prevention Project)

The shrimp were introduced into the lake in the 1960s, and now inhabit its waters, according to a press release from the university. The problem is that they eat native zooplankton that historically helped keep the lake waters blue and clear.

Researchers noticed that when the shrimp disappeared from part of the lake for an unknown reason in 2011, the zooplankton flourished and clarity in the water increased by almost 40 feet over a two-year period. When the shrimp mysteriously reappeared, the water clarity tanked again.

"Even with climate change, we’re finding that if you get rid of the shrimp, clarity improves," Geoffrey Schladow, director of UC Davis TERC and a professor in the College of Engineering, said in the press release. "Their removal allows for the return of native zooplankton, which have the ability to consume both tiny algae and fine clay particles that have reduced clarity in the past. That is huge."

Scientists from UC Davis' Tahoe Environmental Research Center night-trawl for invasive Mysis shrimp in a quest to eliminate them from the lake.

(UC Davis TERC)

In response, TERC launched a two-year pilot program in 2018 to trawl for shrimp and determine a way to remove enough of them to make a difference.

The lake's air and water temperatures have been rising since 1968, when official record-keeping started. Temperatures in the Tahoe Basin are expected to be up to 9 degrees warmer than today's average by the end of the century, according to the report.

The lake had one of its warmest daily summer surface water temperatures ever, 77.5 degrees, on Aug. 6, 2018.

Warmer waters promote the growth of algae, which impacts water clarity, and , according to Keep Tahoe Blue.

Schladow said eliminating the shrimp could help mitigate those effects.

"The efforts long underway in the Tahoe Basin to improve lake health and clarity have been and continue to be important," he said. "Maintaining and building resiliency requires many solutions working together, as well as more tools in our toolbox than we’ve currently been using. That’s one reason we find this ecological solution to be so exciting. Our clarity goals don’t have to be derailed by climate change."