Grizzly Island Wildlife Area

NOTICE: The Joice Island Unit of Grizzly Island Wildlife Area will have hunt access for Joice Island reservations on a week by week basis depending upon progress of the bridge construction. Hunters with reservations can call the office, 707-425-3828, on Wednesday, Thursday or Friday before their hunt for the latest update.


With 88,000 acres of land, bays and sloughs, the Suisun Marsh is significant: it is the largest contiguous estuarine marsh in the entire United States. Grizzly Island Wildlife Area is approximately 12,900 acres of this prime habitat and the complex is a patchwork of 10 distinct land parcels, many of which are not connected and are surrounded by private land. Units include Grizzly Island, Crescent, Joice Island, Island Slough, Gold Hills, West Family, Goodyear Slough, and Grey Goose. They offer a variety of recreation opportunities and act as a vital buffer against further marsh development.

The complex combines natural tidal wetlands and artificially diked marshes. Each habitat attracts a special kind of wildlife. Pass some hours along the bay or on the graveled foot trails at Peytonia Slough. Experience the renewing rhythm of the tides, the changing complexion of marsh life. Some animals, like the California clapper rail and Suisun shrew, live exclusively in these tidal wetlands. Rare, threatened and endangered species include the salt marsh harvest mouse, peregrine falcon, California Ridgway's rail, California black rail, bald eagle, Suisun aster, and soft-haired birds beak.

CDFW staff manage extensive waterways and pumps to create more than 12,000 acres of seasonal ponds. Plants like alkali bulrush and fat-hen are encouraged. This carefully managed combination of high nutrient food and resting ponds sustains more than 100,000 waterfowl that winter at Grizzly Island each year.

For more information, call the wildlife area at (707) 425-3828, or the Bay Delta Region Fairfield office at (707) 428-2002.

Recreational Opportunities

wildlife viewing hiking fishing deer hunting restrooms disabled access information kiosk or visitor center

Grizzly Island occasionally closes in the winter due to flooding. Please call (707) 425-3828 to check for closures before visiting.

Hours: The Headquarters Office is open Monday-Friday, 8:00 a.m. - 4:30 p.m.

Activities: nature viewing, hiking, photography, dog training, fishing, and hunting

The remarkable mix of marsh scenery and wildlife has attracted nature lovers, hunters, anglers and others for decades. Boats and canoes drift easily on the tidal sloughs. There are 75 miles of roads and trails, and several self-guided hiking trails are being planned. See the Seasonal Guide (PDF) and Self-guided Tour (PDF).

Hunting: Waterfowl, dove, pheasant, tule elk, and rabbit may be present.

Facilities: Access roads, parking areas, restrooms, public phone, maps and literature. Disabled access is available for nature viewing, angling, and waterfowl hunting.

NOTE: Visitors are responsible for knowing and complying with all regulations pertaining to the use of Department lands.

Refer to the Public Uses on State and Federal Lands section of the Waterfowl, Upland Game, and Public Use Regulations (PDF) booklet for both statewide and property-specific regulations.

no drones icon
You may not operate a drone on CDFW Lands without a Special Use Permit.

Closure Information

The Grizzly Island Wildlife Area is closed to all non-hunting uses beginning in late July for the tule elk hunt through the end of waterfowl hunt season in early February. Please call (707) 425-3828 for the exact closure dates.

During the annual closure, we recommend visiting the following alternative areas within the Suisun Marsh for hiking, photography, nature viewing, and fishing opportunities:

  • Hill Slough Wildlife Area: located on Grizzly Island Road, right off of Highway 12 in Suisun, before the bridge.
  • Peytonia Slough Ecological Reserve: located at the foot of Kellogg Street in Suisun City, near the marina.
  • Belden's Landing Fishing Access and Boat Launch Ramp, located on Grizzly Island Road.

Hunting Opportunities

There are approximately 7,900 acres open to hunting, including a free-roam area at Island Slough (450 acres), (10) assigned blinds at Goodyear Slough (70 acres), Grey Goose (73 acres). Special access blind sites are available at two Units for mobility impaired hunters.

Type A: Grizzly Island Unit, Crescent Unit, and Joice Island Unit have restricted hunter access during waterfowl and pheasant hunting seasons. Adult hunters are required to purchase in advance a Type A hunting pass in order to exchange for an entry permit. For Type A units, all hunters must check in and out at the "hunter check station" on Grizzly Island Road, located approximately 11 miles from Highway 12. The station usually opens two hours before shoot time. Entry permits and maps are obtained here.

Type B: Goodyear Slough Unit, Island Slough Unit, and West Family Unit require adult hunters to purchase in advance a Type A or B season hunting pass for waterfowl and pheasant hunting for all authorized shoot days of the season. Reservations are required for the opening weekend of waterfowl season for Type B wildlife areas and may be required for the opening of pheasant season.

Type C: Grey Goose Unit does not require the purchase of a hunting pass for entry. Entry permits and/or passes or special drawing may be required for hunting on some Type C wildlife areas.

Rabbit: Hunters must fill out a free daily permit at the Visitor's Registration Booth. A map is available showing areas that are open and closed for rabbit hunting.

Elk: Special hunts for tule elk are conducted in most years during August and September on the Grizzly Island Unit. Hunt information and application form can be found in CDFW publication Big Game Hunting which is available annually in late April. Also, see the Mammal Hunting Booklet on the CDFW Regulations page for specific information.

Hunters are strongly encouraged to bring one non-hunting companion for assistance. There is a mandatory hunter orientation prior to hunt day.

Waterfowl: Please refer to the CDFW Waterfowl Hunting page for more information on applying for reservations in advance. The West Family Unit is for junior hunting and includes six designated first-come, first-served blinds.

Junior Pheasant Hunt (Game Bird Heritage Hunt): Each year on the second weekend of the season, an area of the Grizzly Island Unit is set aside for junior hunters. Call for reservations. No fee.

Special Hunts: See the Special Hunts Online Registration System.

Joice Island Wild Pig Hunts: CDFW offers wild pig hunting opportunities in March, April and May at the Joice Island Unit of the Grizzly Island Wildlife Area in Solano County. See Joice Island Wild Pig Hunt Information.


Fishing Opportunities

At various times of the year several species of game fish may be caught at Grizzly Island. They include striped bass, brown bullhead, white catfish, white sturgeon, black crappie and the occasional largemouth bass, Chinook salmon and steelhead. Fish may be caught in Montezuma slough or within many of the interior waters of the island depending on closures for other activities (See Public Use Schedule). During closures at Grizzly Island you may still fish at Hill Slough Wildlife Area, Belden's Landing and the Island Slough Unit.

Striped bass used to be seasonal in their movements with runs in spring and fall. Currently they appear to be more erratic and fish may be caught at any time of year. Fishermen catch stripers while bait fishing with anchovies or bullheads but also using artificial lures like lead head jigs, lipless crankbaits and others. Sturgeon are more regular, generally occurring in greatest numbers with the late winter rains and spring runoff, especially when they coincide with the higher tides during this time of year. Catfish or bullheads may be caught any time of year with many anglers using clams, anchovies or chicken gizzards for bait. Crappie and Largemouth Bass are spotty in their distribution on Grizzly Island. Time of greatest abundance appears to be in spring and early summer when the normally brackish waters of the Suisun Marsh are at their freshest.

To obtain a copy of CDFW's Striped Bass Fishing Map, which includes the Suisun Marsh and surrounding Delta Region, please call (209) 234-3420.

Area History

When the western reaches of the Sacramento and San Joaquin rivers blend with ocean tides, they form a great marsh -- "the place of the west wind". "Suisun" was the name given to this marsh centuries ago by the Patwin Indians. Grizzly Island Wildlife Area lies in the heart of this sprawling wetland.

Long before gold and fertile soil called people with dreams west, it was a haven for wildlife. Millions of migratory waterfowl and birds wintered there. Its tule-lined ponds were a home for hundreds of wildlife species, including California's native tule elk and grizzly bear.

This began to change in 1850, when the U.S. Congress granted all such swamps, marshes and sloughs to the state of California, so they could be drained for cultivation. Natural tidal rhythms were permanently altered by levees and dikes constructed to prevent salt water from reaching cultivated land. Much of the area was carved into parcels and sold to private interests for farming.

From 1875 until 1950, this area that once nourished so much wildlife grew other things: dairy cattle, beans, grains, beets and asparagus. Small duck clubs were interspersed among the farms.

But local landowners, even with their labyrinth of channels, levees and sloughs, could not prevent the encroachment of salty water or the deterioration of constructed levees. In 1931, the California Department of Fish and Wildlife (CDFW) purchased a parcel known as Joice Island, naming it one of California's first wildlife refuges.

As other landowners became discouraged, duck clubs provided additional habitat for wildlife and both proliferated. In 1950, CDFW purchased an 8,600-acre parcel near Joice Island. Called the Grizzly Island Unit, it nicely complemented the Joice Island refuge.

Some locals are convinced this unusual name came from the Mt. Diablo grizzly bears that used to swim across the bay to feast on the lush blackberries and rosehips on the island. Others insist the name is a corruption of the word "grisly", which was used to describe frightening things that occurred in this once-swampy, inhospitable place.

Today, there are neither grizzly bears nor grisly events at Grizzly Island Wildlife Area... but there is an opportunity to enjoy a rewarding wildlife experience just an hour from San Francisco or Sacramento.

Map of Grizzly Island WA - click to enlarge in new window
Click to enlarge


Bay Delta Region (Region 3)

Solano County

within the Suisun Marsh

2548 Grizzly Island Road
Suisun, CA 94585

Directions: Take 1-80 north from San Francisco, south from Sacramento. Take Highway 12 off-ramp east toward Rio Vista. Turn onto Grizzly Island Road, at the stoplight at Sunset Shopping Center. Hill Slough Wildlife Area is on both sides of Grizzly Island Road from Highway 12 to the first one-lane bridge. The Grizzly Island Complex Headquarters is 9.5 miles further on Grizzly Island Road.

Units: Joice Island and Island Slough Units are on Grizzly Island Road. Island Slough Unit is approximately seven miles from Highway 12. Gold Hills, West Family, and Goodyear Slough Units can be reached from I-680. For Goodyear Slough, take the Lake Herman Road exit. Grey Goose Unit can only be accessed by boat from Suisun Slough to Boynton Slough.

Nearby Attractions: Brannan Island State Park, Rush Ranch, Jepson Prairie Preserve, Lagoon Valley Lake, Rockville Hills Park

Public Use Map (PDF)

CDFW Lands Viewer