Campfires are restricted year-round on the Sunnyside-Snake River Wildlife Area.
The Thornton Unit is a popular hunting area for deer and is one of the best places on the wildlife area for the public to hunt elk. This property was acquired for mule deer, upland birds, transitory elk (the Rattlesnake Hills herd), Greater sage grouse, and other shrubsteppe-obligate species.
The Thornton Unit is located 8 miles northeast of Prosser on the west side of Benton County. It is also about 3 miles west of WDFW's Rattlesnake Slope Unit. The Thornton Unit can be accessed from Rothrock Road on the west side and Case Road on the east side.
The Thornton Unit is located within the Lower Yakima River watershed in the Columbia Plateau. This unit shares a 2-mile boundary with Department of Natural Resource land, and lies just south of the Hanford National Monument managed by the U.S. Fish and Wildlife Service.
This unit is part of the Sunnyside-Snake River Wildlife Area.
Game Management Unit: 372
Getting there
Maps and directions to WDFW-managed access points for this unit. Opens Google Maps in a new tab.
Recreation and public access
A Discover Pass is required on WDFW lands -- including water access areas, wildlife areas, and campgrounds -- unless you already have a Vehicle Access Pass issued with the purchase of an eligible hunting or fishing license. Recreate responsibly on public lands: please know the Public Conduct Rules.
Public facility information:
- Gravel parking areas
- No restroom
Recreation and access advisories
- No open fires permitted.
- No overnight camping permitted.
Hunting
The unit is a popular hunting area for deer and is one of the best units of the Sunnyside-Snake River Wildlife Area for the public to hunt elk.
Wildlife viewing
This unit includes shrubsteppe intermixed with retired wheat fields (now native grass), Snipes Creek, riparian habitat, canyons, and springs, offering opportunities to view elk, mule deer, Greater sage grouse, and other wildlife.
Search for potential birding opportunities on or near a wildlife area unit by using eBird Northwest, a citizen science database portal that provides freely-shared bird lists at 'hotspots' and interactive maps plus other birding information updated daily.
Wildlife viewing advisories
- Greater sage grouse (state-listed threatened species) are sensitive to human disturbance. Do not flush or otherwise disturb these birds.
Conservation
This unit has shrubsteppe intermixed with grass (Conservation Reserve Program) fields. Several canyons cross the property, generally from north to south. This unit supports long ridges of good quality shrubsteppe with abundant spring wildflowers, intermixed with the former wheat fields. By 1999, all 1,300 acres of croplands had been converted to native-like grasslands. Currently, most intermittent water disappears by mid-summer. Snipes Creek bisects the unit and provides limited but important riparian habitat in places. A spring in the center of this unit provides free water nearly year-round and other smaller springs exist in other canyons.
Special habitats and species
Greater sage grouse and other shrubsteppe-obligate species benefit from shrubsteppe habitat.
Conservation goals
- Maintain agriculture leases to benefit migrating waterfowl, upland birds, and Sandhill cranes
- Maintain and increase moist soil management
- Maintain and restore shrubsteppe, upland and floodplain habitat
- Protect and enhance habitat for state and federal listed species
- Maintain and restore wetland habitat
Greater sage grouse and other shrubsteppe-obligate species benefit from shrubsteppe habitat.
- Maintain agriculture leases to benefit migrating waterfowl, upland birds, and Sandhill cranes
- Maintain and increase moist soil management
- Maintain and restore shrubsteppe, upland and floodplain habitat
- Protect and enhance habitat for state and federal listed species
- Maintain and restore wetland habitat
Land stewardship
The Thornton Unit was acquired for mule deer, upland birds, transitory elk (the Rattlesnake Hills herd), sage grouse, and other shrubsteppe-obligate species.
Acquisition history
The parcels making up this area were purchased in 1994.
| Funder | Fund |
|---|---|
| WA Dept of Fish and Wildlife | WDFW Game Fund (now Wildlife Fund) |
Management planning
2020 Sunnyside-Snake River Wildlife Area Management Plan
Every eight to 10 years, the Washington Department of Fish and Wildlife (WDFW) revises management plans for each of its 33 wildlife areas to document current conditions, address new agency initiatives, and identify new management priorities and actions. In between those major revisions, WDFW updates plans every two years to outline short-term objectives and accomplishments. In 2014, WDFW began the process of updating existing plans, many of which were written in 2006. The new plans are being developed with significant public participation and input.
Planning Advisory Committee
Sunnyside-Snake River Wildlife Area Advisory Committee