The number of Tahoe yellow cress occurrences around the lake correlates directly with fluctuating lake levels. Wide expanses of beach are available for colonization and the number of occupied sites is generally high when the lake is low. When the lake rises, less habitat is available and the number of occupied sites declines. As the amount of available habitat declines pressure from recreation intensifies in the remaining beach habitat. It is this recurrent combination of high lake levels and increased trampling from recreational beach use that pose a continued threat to TYC.
The Adaptive Management Approach
Adaptive management uses a “learning by doing” approach. The process is iterative, usually portrayed as a cycle of strategy, design, implementation, monitoring, evaluation and decision-making. Management actions are evaluated using carefully designed monitoring and modifications to management actions are in turn tested with updated monitoring protocols. With each turn of the cycle, active learning through monitoring and evaluation reduces management uncertainties by developing tools that prove beneficial to Tahoe yellow cress’ survival.
Adoption of the Conservation Strategy in 2002 launched the adaptive management phase of Tahoe yellow cress. It specifies an adaptive management process and a focused research agenda to assist land and resource managers in meeting the recovery needs of TYC. The Adaptive Management Working Group (AMWG) is the workhorse of the TYC adaptive management process as it carries out the duties of budget oversight, conveyance of decisions to affected parties, prioritization of research and monitoring tasks and long-term planning. It provides the direct communication conduit for all affected agencies, local governments and private entities and it is through the AMWG that adaptive management becomes a community learning process.