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.
This unassuming and unsung area holds some of the greatest raptor concentrations in the region. The rice fields can host immense flocks of Snow and Greater White-fronted Geese, and Tundra Swan. When water conditions are right, the shorebirds can be very good.
A walk through the sanctuary is a delight in any season. Over 195 species of birds have been recorded. In summer, Swainson’s Hawk soar overhead. Great Horned Owl is common here. Wood Duck, herons, egrets, and Pied-billed Grebe can be found year-round. Springtime brings a variety of warblers as well as nesting Western Bluebird, Bullock’s Oriole, and Black-headed Grosbeak. In winter, sparrows, towhees, kinglet, Yellow-rumped Warbler, and Northern Flicker are among the common birds.
Approximately 1 hour north of Sacramento, the Colusa NWR is a great location to view large waterfowl concentrations, especially during December and January.
In winter, you will often see the sky at Gray Lodge filled with geese and ducks. Snow Geese, as well as the greatest concentration of Ross's Geese in the United States, are found here along with Greater White-fronted Geese and Canada Geese.
From October through March, many fields in this area contain Sandhill Cranes in varying numbers, with the best time for observation occurring during January, February, and March when some fields are flooded, and there are also large numbers of wintering shorebirds and waterfowl.
Staten Island is another excellent site for viewing large numbers of Sandhill Cranes, geese, Tundra Swans, other waterfowl, and shorebirds.
This magnet for birds on the Solano-Yolo County line is formed by a small diversion dam on Putah Creek several miles east of Lake Berryessa and the Vaca Mountains, the eastern-most ridge of the North Coast Ranges. For best birding, visit the area early in the morning; fall and winter are most productive, due to the arrival of winter visitors.