Combating Lake Tahoe's Invasive Clams With Rubber Mats

Death by rubber mat -- this is the unconventional method scientists are using to combat escalating Asian clam populations in Lake Tahoe. 

The invasive clams (Corbicula fluminea) arrived in the famous mountain lake in 2002. It's unclear exactly how the clams infiltrated the lake, but humans are likely to blame -- boats transported from another lake could have easily toted along the unwelcome guests.

Since their arrival, their population has skyrocketed at the expense of native snail and clam species. 

A University of California Davis press release reported that some regions of the lake bed, such as the California-Nevada state line, have thousands of Asian clams per square yard. 

Researcher Geoffrey Schladow and others from UC Davis are targeting these heavily infested regions for their tarp experiment. By covering the clams with rubber mats, Schladow hopes to isolate and suffocate them.

Unfortunately, some native species will also be sacrificed. 

“We will be killing everything that is under the mats -- not so much plants, but invasive animals (the clams) and the native clams and other organisms," Schladow told Discovery News. "There is no way around this.”

“Last summer our tests showed that we killed 10% of the native clams and 98% of the invasive clams,” Schladow continued. Killing off some native animals is a necessary consequence to supporting these species in the long run.

In addition to messing up Tahoe’s natural food chain, Asian clams threaten the lake’s prized azure color. The pesky clams support the growth of bright green algae, which makes the water murky and can low the oxygen content of the water.

In September, researchers will remove the tarps. Schladow is optimistic that the mats will kill the invasive clams, but he doesn't know if the clams will stay gone, or make a rapid comeback.

If everything goes according to plan, the native clams will recolonize the cleansed lake floor, restoring order and clarity. 

Image: USGS, Wikipedia