The Nimbus Dam creates a narrow reservoir below Folsom Lake on the American River. It backs up water for nearly six miles, starting just upstream from the Nimbus Hatchery and the Hazel Avenue bridge. Open water attracts many water birds and the surrounding oak woodlands add to the species diversity.
The multiple locations described in this section (Folsom Point, Mormon Island Wetlands, Morman Island Lake Access, Brown’s Ravine, Falcon Crest, Sweetwater Creek trail to Folsom Lake, and Sweetwater Trail) can be done as individual short excursions or as a full day of birding, progressing from one stop to the next.
Beals Point is probably the single best location for viewing large numbers of gulls and water birds on Folsom Lake. From 3pm until dusk thousands of gulls flying in to roost on the lake. As many as 14 Common Loons have been recorded just from this site.
Beeks Bight offers foothill woodland habitat dominated by interior live oak, gray pine, and blue oak. The spring season provides the greatest diversity. Dozens of migrating and resident hummingbirds can be found feeding on flowers. Granite rock outcroppings prevail throughout and offer excellent habitat for Rock Wrens and Rufous-crowned Sparrows.
An afternoon hike in this area on a clear day in the middle of January will reward the birdwatcher with sunshine, green foothill grasses, early blooming manzanita and coyote bush, and over 60 common species of birds. This is also the best time of year for sighting Bald Eagles and Osprey soaring along the lake’s shoreline.
The peninsula between the north and south arm of Folsom Lake is the most remote and under birded portion of the recreation area. Possibilities include California Thrasher, Lewis’s Woodpecker and rarely Bell’s Sparrow. Burrowing Owls have been found sheltering among the rocks on a few occasions.