No Subcategories for this Indicator.
Program Tahoe Yellow Cress Monitoring
Knowledge of TYC distribution has been developed through shorezone surveys since 1979. Before 2000, surveys followed a general protocol and were completed at various times during the summer. Since 2001, surveys are conducted the first week of September following a standardized protocol. During the first survey in 1979, 32 TYC sites were surveyed; this has since grown to 55 sites. A survey “site” is defined as a stretch of public beach, adjacent private parcels, or adjacent parcels under a combination of private and public ownership. Surveys include stem count estimates as a measure of TYC abundance because clonal growth makes it impossible to distinguish individuals. The amount of available shorezone habitat for TYC fluctuates widely with changes in lake level, with high lake levels leaving little habitat. On average, over 70% of surveyed sites are occupied when the lake is below 6,225 ft. in September, but less than 40% are occupied when the lake level is above 6,228 ft.
To download all of the Tahoe yellow cress data on this page please see Tahoe Open Data.
Associated Programs data not provided.
Tahoe Yellow Cress (Rorippa Subumbellata) is include in the Threshold Dashboard. Threshold Indicators are evaluated against Threshold Standards every 4 years. Thresholds are environmental goals and standards for the Lake Tahoe Basin that indirectly define the capacity of the Region to accommodate additional land development.