Description - This refuge consists of nearly 5,800 acres of intensively managed land in Colusa County. Wetlands comprise about 78% of the total acreage and approximately 1,250 acres are in upland.
- Delevan NWR is part of the Sacramento NWR Complex and is located in the Sacramento Valley of north-central California. The refuge consists of nearly 5,800 acres comprised of seasonal marsh, permanent ponds, watergrass, and uplands in Colusa County.
Central Valley wetlands are critical to Pacific Flyway waterfowl, as 44% winter in the Sacramento Valley. As a result, the marsh management program is one of the most intensive in the refuge system. The refuge supports wintering populations over 200,000 ducks and 100,000 geese. As wetlands of the Central Valley have been lost (95% over the last 100 years), waterfowl have become increasingly dependent on the Sacramento Valley refuges.
Waterfowl are present from September through March, and hundreds of thousands of ducks and geese from November through January. Numerous birds and mammals are present year round.
Recreation - Recreation activities include wildlife observation, study, and photography from perimeter roads. Hunting of ducks, geese, coots, snipe, and pheasants is permitted October through January on Saturdays, Sundays, and Wednesdays. The spaced hunt site area has 10x20 foot islands.
Climate - A generally warm, dry climate prevails in the Central Valley. It is hot in the summer, mid in the winter. In the Central Valley, precipitation falls mainly from October through April. Winter temperatures well below freezing produce frost, however, snow is very rare. Summer temperatures above 100 F are part of the normal pattern.
The refuge is situated about 80 miles north of Sacramento and four miles east of the town of Maxwell. From Interstate 5, exit Maxwell Rd., approximately 9 miles north of Williams. Continue east to Four Mile Rd., which parallels the west refuge boundary.