Each winter, more than 100,000 waterfowl settle into the managed ponds of the Grizzly Island Wildlife Area. For most of those months, anyone without a hunting reason can't get in. The California Department of Fish and Wildlife closes the wildlife area to all non-hunting uses starting in late July, when the tule elk hunt begins, and keeps it closed through the end of waterfowl season in early February. So the best stretch of the marsh year and the longest locked gate cover the same months.
None of that leaves Suisun City without a marsh. For the next three months, the public part of the Suisun Marsh is the edge closest to town: a ranch two miles down Grizzly Island Road, a wildlife area just past Highway 12, and a reserve at the foot of Kellogg Street near the marina. You can walk the winter marsh without driving to the end of the road.
The gate and the birds keep the same calendar
The size of the closure explains why the edges matter. CDFW describes the Suisun Marsh as 88,000 acres of land, bays and sloughs, the largest contiguous estuarine marsh in the United States. Grizzly Island Wildlife Area covers about 12,900 acres of it, and staff manage pumps and waterways to create more than 12,000 acres of seasonal ponds. Those ponds are what draw the winter waterfowl.
The agency doesn't print fixed annual dates for the closure. Its notice asks visitors to call 707-425-3828 or email [email protected] for exact dates. The same page warns that Grizzly Island sometimes closes in winter because of flooding, so the call is worth making even after the hunt season ends. The notice also names three places to go instead. Two are on Grizzly Island Road and one is near the Suisun City marina. Rush Ranch, the most developed public site on that stretch of road, isn't on CDFW's list because it isn't CDFW land.
Rush Ranch changes its hours on November 1
Rush Ranch Open Space is at 3521 Grizzly Island Road, about two miles south of Suisun City, with parking and restrooms at the main entrance. It's open seven days a week all year. Sunday, November 1 is the first day of winter hours, 8 a.m. to 5 p.m., which run through February 28. Until then it closes at 7 p.m. Saturday, October 31 is the last day with a 7 p.m. closing. From Sunday on, an after-work walk has to end by 5.
The ranch is worth visiting in winter because of a decision the Rush family made. According to Solano Land Trust, the family ran the property for most of the 20th century and, unlike neighboring landowners, never diked the marsh or otherwise significantly changed its tidal flow. The marsh still rises and falls with the tides, and that is why it became so useful to tidal marsh science. Solano Land Trust bought the ranch in 1988 with a Coastal Conservancy grant. In 2003 it became part of the San Francisco Bay National Estuarine Research Reserve. Most of the Suisun Marsh you see from a car is managed ponds. At Rush Ranch you're looking at marsh that still works the way it naturally does.
The trust lists more than three miles of trails:
- Marsh Trail, a flat, accessible path with wide views of the Suisun Marsh
- South Pasture Trail, through rolling grassland
- Hill Slough Trail, the harder hike, with panoramic views
Before you load the car, know two rules. Dogs are allowed on leash only on the Suisun Hill Trail, the entrance road and around the ranch buildings, and they're not allowed on the Marsh Trail or the South Pasture Trail. Fishing, hunting, off-road vehicles and drones are all prohibited. The Marsh Trail is also closed where it crosses the levee to Goat Island. The trust says the levee has degraded in several places beyond what small repairs can fix, and that it is weighing public access options with its National Estuarine Research Reserve partners as part of a larger plan to restore Goat Island Marsh. It is asking for public comment. Plan on a shorter Marsh Trail loop than older maps show.
As for wildlife, the trust names the white-tailed kite, great blue heron and marsh wren among the ranch's birds. It also lists the salt marsh harvest mouse, an endangered species found only in tidal wetlands.
Two Saturdays with a guide
Rush Ranch holds its free "Get the Rush!" program on the third Saturday of each month. The wagon rides ran through October 2026, so they won't be part of the winter dates. The rest of the morning continues.
| Date | Hours | Guided marsh walk | What's open |
|---|---|---|---|
| Saturday, November 21, 2026 | 10 a.m. to 12:30 p.m. | Starts 10:30 a.m. | Blacksmith shop, Rush Ranch Outfitter's shop, exhibit tables |
| Saturday, December 19, 2026 | 10 a.m. to 12:30 p.m. | Starts 10:30 a.m. | Blacksmith shop, Rush Ranch Outfitter's shop, exhibit tables |
Registration is recommended for the marsh walk, and rain cancels the event. You can sign up on the November event page or the December event page. The trust also partners with the Rush Ranch Educational Council, an all-volunteer nonprofit that runs education and public outreach programs at the ranch.
Three CDFW alternatives on the town side of the marsh
CDFW's list of substitutes during the closure is short, and each entry carries a location in or just outside Suisun City. Each one offers something different.
Hill Slough Wildlife Area is on Grizzly Island Road just off Highway 12, before the bridge. It covers roughly 1,700 acres of marsh and grassland, with wildlife viewing and hiking trails and no facilities listed. CDFW's species list there reads like a winter field guide: pintail, mallard, teal and wigeon on the water, and northern harrier, white-tailed kite, kestrel and red-tailed hawk overhead. With no restrooms on site, it suits a short visit. CDFW is also drafting a joint long-term land management plan for Hill Slough and Grizzly Island.
Peytonia Slough Ecological Reserve is the closest to downtown. CDFW places it at the foot of Kellogg Street near the marina. CDFW's two pages describe getting in differently. The Grizzly Island page suggests spending a few hours on the graveled foot trails at Peytonia Slough. The reserve's own page lists hiking, fishing and wildlife viewing but describes access by boat from Suisun Slough, with the ramp, restrooms and parking at the neighboring Suisun City Boat Launch. If you plan to arrive on foot, check with CDFW first.
Belden's Landing is a Solano County site on Grizzly Island Road with a boat launch onto Montezuma Slough and both bank and pier fishing. The county has posted an improvement concept and is asking for feedback while it looks for future funding. For now it's a working fishing and launch site, not a trailhead.
Together with Rush Ranch, these four sites give you a winter marsh for any kind of visit. Hill Slough works for a quick raptor check off the highway. Peytonia is the one next to the marina. Belden's is for a line in Montezuma Slough or a boat launch. Rush Ranch has the trails, restrooms and Saturday guides.
December 14: the count that covers Suisun's side of the marsh
The closure shuts visitors out of Grizzly Island, but the island still falls inside a winter bird census. Napa-Solano Audubon lists the 79th Benicia Christmas Bird Count for Monday, December 14, 2026, on its chapter calendar. According to the chapter's Benicia count page, the count circle takes in west Suisun City and parts of Grizzly Island and Grizzly Bay. Anyone who wants to join should contact the chapter for 2026 sign-up details and route assignments.
The chapter also runs weekly Saturday walks at parks and open spaces around Napa and Solano counties, with the location changing from week to week. The published schedule is the place to check whether a walk lands on the Suisun side of the marsh this season.
The weekend before the hours change
The first marsh weekend of the season overlaps with two free events in town. The Suisun City Fire Department Halloween Parade runs Saturday, October 31, from 3:30 to 5 p.m. at Main Street and Driftwood Drive downtown. The next day, Sunday, November 1, the city's Día de los Muertos Celebration runs from 4 to 8 p.m. at the Joseph Nelson Community Center, 611 Village Drive, with ofrendas, Ballet Folklórico, music, food and vendors.
November 1 is also the first day of Rush Ranch's 5 p.m. closing. A Sunday that starts on the Rush Ranch trails at 8 a.m. can still end at Joseph Nelson Community Center by 4.
CDFW's notice puts the end of the Grizzly Island closure at the close of waterfowl season in early February. The wildlife area's line at 707-425-3828 has the exact date.
Suisun City's marsh edge, from the Kellogg Street waterfront to the ranches along Grizzly Island Road, is land the Carmen Gray Team follows closely across Solano County. If you own open space, waterfront or agricultural property near the Suisun Marsh and want a discreet read on what it is worth today, request a private consultation.
