An invasive species was found in Lake Tahoe. Here’s what they look like and how you can help

Invasive New Zealand mudsnails have been detected for the first time in the Tahoe Basin.

The tiny aquatic snails were discovered by divers near Lake Tahoe’s southern shore — about half a mile from the Upper Truckee River. An expert consultation and lab analysis confirmed the DNA, Tahoe Regional Planning Agency wrote in a news release. It has also been detected in nearby waterways near Reno.

It’s not known how the creatures wound up in Tahoe, according to a announcement from the Tahoe Regional Planning Agency and the Tahoe Resource Conservation District, though other species have been introduced through contaminated boats and other aquatic equipment.

“It is critical that everyone remain vigilant and adhere to the mantra of Clean, Drain, and Dry,” said Julie Regan, executive director of the planning agency. This refers to the upkeep of boats and gear — including fishing gear, life vests and paddles — by clearing them off before entering new waterways. “Every boater, paddler and angler shares the responsibility to protect Lake Tahoe’s native species and the waters we enjoy.”

Since the mudsnails were discovered, scientists have been doing water dive surveys to assess the extent of the infestation and sharing their findings with the Lake Tahoe Aquatic Invasive Species Coordinating Committee. Rapid response was necessary because the snails could easily displace native species for resources and harm the ecosystem.

“Every boater, paddler, and angler shares the responsibility to protect Lake Tahoe’s native species and the waters we enjoy,” Regan wrote in a news release.

The creatures are typically smaller than a grain of rice, averaging up to between 4 and 6 millimeters long, according to the California Department of Fish and Wildlife. Their shells vary from gray to brown.

As the name implies, New Zealand mudsnails are native to New Zealand. The “hard to detect” creatures are currently in 22 states across the U.S. including California and Nevadda, according to a news release.

Do not confuse these snails with other invasive species, like dam-destroying quagga and zebra mussels.

A team of experts with the Tahoe Regional Planning Agency and Conservation District is conducting further dives to determine “the extent of the infestation.”

“The incident team and our partners are dedicated to protecting Lake Tahoe and will be working together to evaluate options for responding to this new finding,” said Dennis Zabaglo, the aquatic invasive species program manager for the Regional Planning Agency.

This story was originally published September 21, 2023 at 2:54 PM.