A partnership between Oregon State University, Real Time Research, and the USGS - Oregon Cooperative Fish and Wildlife Research Unit

Fern Ridge Reservoir

Tern nesting island in Fern Ridge LakeFern Ridge Reservoir is a shallow and expansive flood control reservoir in the southern Willamette Valley near the City of Eugene (OR), owned and managed by the U.S. Army Corps of Engineers. Although Caspian terns have been observed to use the reservoir during migration, terns have not previously nested at the site. In 2008, the U.S. Army Corps of Engineers began implementing the plan “Caspian Tern Management to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary,” described in the Final Environmental Impact Statement (FEIS) and Records of Decision (RODs) signed in November 2006. This management plan seeks to redistribute a portion of the East Sand Island tern colony to alternative colony sites in Oregon and California by 2015. Fern Ridge Reservoir is one of five sites in Interior Oregon/N.E. California where resource managers intend to create nesting habitat for Caspian terns as part of this plan. In February 2008, the U.S. Army Corps of Engineers completed construction of a 1 acre island in Fern Ridge Reservoir near the Fern Ridge Wildlife Area, which is managed jointly by the Oregon Department of Fish and Wildlife and the Corps of Engineers. The island was revetted with rip-rap to prevent erosion and topped with pea gravel as a nesting substrate for Caspian terns. Caspian tern decoys and audio systems that broadcast Caspian tern calls were installed on the island in an effort to attract terns to nest at the site. Although Caspian terns frequently visited the island after the breeding seasons in 2008 and 2009 (presumably post-breeding terns that dispersed from other nesting sites), terns did not attempt to nest there during those years, possibly due to avian predation and human disturbance at the site.