15-year-long partnership keeps Tahoe Yellow Cress off endangered species list

Successful conservation actions from a collaborative Lake Tahoe partnership spanning the past 15 years have helped the U.S. Fish and Wildlife Service decide today that Tahoe yellow cress (Rorippa subumbellata), a flowering perennial plant in the mustard family found only along the lake’s sandy shoreline, does not warrant federal protection under the Endangered Species Act (ESA).

They decided to remove the plant from the ESA candidate species list after an analysis of the best available scientific and commercial data showed that previously identified habitat threats along the lake’s shore no longer pose a significant risk to the health and persistence of the species. The significant reduction of those threats was guided by a proactive conservation strategy developed in 1999 and implemented in 2002 by a consortium of federal and California and Nevada state, local and private partners that remained committed to conserving the plant’s unique ecosystem, thereby eliminating the need for federal regulation under the ESA.

“The efforts of the Lake Tahoe area working group and its technical team and the partnerships they’ve built over the past decade to protect this unique plant have truly exemplified the most basic function of the ESA – to protect and conserve ecosystems and the species that depend upon them,” said Ted Koch, Reno Fish and Wildlife Office Field Supervisor. “They have continued to raise the standards for the next generation of conservation and convinced us that Tahoe yellow cress has a bright future on the beautiful shores of Lake Tahoe.”

Tahoe yellow cress is a low-growing, herbaceous perennial in the mustard family. Its leaves are fleshy, oblong-shaped and pinnately lobed, or resembling a feather. Its flowers are yellow with small, plump, round fruits. Due to the continual annual fluctuation of Lake Tahoe water levels, much variability in the amount of suitable and occupied habitat exists for the species. However, during the most recent, on-the-ground survey in 2014, biologists found the species thriving at 36 of the 49 habitat sites they studied.

The Service declared Tahoe yellow cress a candidate species under the ESA in 1980, but removed it from the list in 1996, when a period of lower lake elevations exposed its crucial, sandy habitat and increased its population estimates. But in 1999, the Service returned the species to candidate status because years of higher lake levels had inundated its habitat, resurrecting concerns for the plant’s limited distribution, small population sizes, and the inability to adequately control human impacts around the shore.

Later that year, the Tahoe yellow cress Technical Advisory Group (TAG) comprised of land managers, regulatory agencies, conservation organizations, and lakefront property owner groups studied the history of the plant and compiled valuable survey data, increasing the group’s understanding of the species’ population dynamics and its conservation needs. From that information, they developed a comprehensive Conservation Strategy for the species, which was finalized in 2002. Since that time, the partners have been meeting quarterly as the Tahoe yellow cress Adaptive Management Working Group, under the oversight of the Tahoe yellow cress Executive Committee.

In January 2003, the Executive Committee signed a Memorandum of Understanding (MOU) to cooperatively implement the strategy for a period of 10 years. These partners include: California Department of Fish and Wildlife, California State Lands Commission, California State Parks, California Tahoe Conservancy, League to Save Lake Tahoe, Nevada Division of Forestry, Nevada Division of State Lands, Nevada Division of State Parks, Nevada Natural Heritage Program, Tahoe Lakefront Owners’ Association, Tahoe Regional Planning Agency, the U.S. Forest Service and the U.S. Fish and Wildlife Service.

In June 2013, a new MOU was signed by the partners that extended the commitment to protect the plant for another 10 years. An updated, revised Conservation Strategy that reflects on actions taken in the past decade and incorporates continued conservation opportunities for the species is expected to be completed by the group within the next few months.

For more detailed information on Tahoe yellow cress and its habitat, along with more information about conservation projects that are being done to help protect this unique species, visit www.tahoeyellowcress.org, or www.fws.gov/cno.