Relevance

The TRPA definition of special interest waterfowl includes species in the Anatidae (i.e., ducks and geese), Ardeidae (e.g., herons), and Sternidae (i.e., terns) families (TRPA 1982b). Protecting habitat for waterfowl also protects habitat for other water birds such as the eared grebe, marsh wren, and Virginia rail (TRPA 2007). The Tahoe Basin supports breeding waterfowl and serves as a stopover for waterfowl migrating along the Pacific Flyway. Many waterfowl species are valued for wildlife viewing and hunting, and collectively they are an important component of functioning wetland ecosystems. Waterfowl are dependent on various biological, chemical, and physical aspects of wetlands for their survival, so their use of a site can serve as an indicator of the biological integrity or relative value of a site for providing a functioning wetland ecosystem.

Human and Environmental Drivers

Many of the mapped waterfowl population sites coincide with recreation destinations (e.g., beaches, golf courses, community parks, and off-highway vehicle and hiking trails). Recreational uses have been demonstrated to reduce reproductive success by causing nest abandonment, decreased hatching success, and reduced survivorship of hatchlings; and can cause mortality by increasing energy expenditures and reducing foraging success (Korschgen and Dahlgren 1992; Knight and Gutzwiller 1995). Physical habitat conditions, such as the type and configuration of vegetation communities and area of open water are good predictors of bird species richness within the basin (Schlesinger and Romsos 2000), so alterations to these physical characteristics could affect waterfowl use of a site. Habitat requirements vary by waterfowl species, but the amount, diversity, and level of alterations to wetlands may be a driver of waterfowl populations (Batt et al. 1992). Historic land uses, such as the filling of large portions of the Upper Truckee Marsh for construction of the Tahoe Keys in the 1960s, has also greatly reduced the amount of waterfowl habitat within the Tahoe Basin. Waterfowl populations in the basin may also be affected by annual and seasonal changes in the availability of food at local, regional and national scales, which can be influenced by weather (e.g., drought). Temporary food scarcity can reduce reproductive success or cause waterfowl to use other areas with more available food resources (Batt et al. 1992).

EIP Action Priorities

• Restore Priority Meadows, Wetlands, and Lake Tahoe Tributaries

  EIP partners are working together to restore several high priority watersheds in the Basin that provide valuable ecosystem service.

EIP Indicators

• Acres of SEZ Restored or Enhanced

  EIP partners have collectively restored or enhanced 1,743 acres of wetlands since 1997.

Example EIP Projects

• Upper Truckee River and Marsh Restoration

  This project will restore and enhance over 250 acres of floodplain by returning river flows to the center of the marsh. Returning river flows to the marsh will enrich native fish and bird habitat.

Monitoring Programs

• Waterfowl Population Site Monitoring

---