Wildlife & Habitat

Browns Park National Wildlife Refuge 512 x 219

Historically, waterfowl were given management priority at Browns Park National Wildlife Refuge. However, Refuge management is now focused on maintaining a variety of native habitats and wildlife with emphasis on all migratory birds, threatened and endangered species, and species of special concern.

Thanks to current management techniques, Refuge habitats support a rich diversity of wildlife species including 68 species of mammals, 15 species of reptiles and amphibians, and at least 223 species of birds.

  • Riparian Habitat

    The riparian habitats found along the Green River, and Vermillion and Beaver Creeks within the Refuge are made up of cottonwoods, buffaloberry, willows, and many other plants that are restricted to flood plains or areas with permanent underground water supplies. Similarly, many wildlife species depend on riparian plants to fulfill their life needs. Thousands of migrating songbirds, like the Lazuli bunting and Wilson’s warbler, rely on riparian habitat for refueling as they travel north to their breeding grounds. Other songbirds, such as the black-chinned hummingbird and Bullock’s oriole, stop to nest. Moose and river otter also raise their young in the riparian area.

    Water development has caused the Refuge riparian habitats to change over time. The riparian area along the Green River has been affected by the Flaming Gorge Dam. Before construction of the dam, the Green River’s water levels responded solely to the uncertainties of nature. Flooding usually occurred in the spring, tapering off to reduced flows in summer. Spring flooding was the primary source of water for the natural wetlands bordering the river.

    After construction of the dam in 1962, people began to control the river flows. Human control has resulted in a decrease in spring floods and a reduction in the amount of sediment carried by the river. This has resulted in the gradual deepening of the river channel, further reducing the likelihood of flooding. This makes it difficult for tree and willow roots to reach water and inhibits the germination of new seedlings within the riparian habitat.

    Field research has confirmed that the riparian cottonwood forests are aging and not being replaced. Instead, nonnative, invasive species such as perennial pepperweed and tamarisk are overtaking this habitat. Pepperweed and tamarisk do not provide forage or appropriate nesting cover for the wildlife species that rely on this area. Research is ongoing to help determine how to increase the regeneration of new cottonwoods and willows in the riparian areas.

  • Wetland Habitat

    The seven wetlands found on the Refuge provide essential foraging and resting grounds for migratory waterfowl during their spring and fall migrations. During the summer, these wetlands provide critical nesting habitat for pied-billed grebes and several species of ducks. Other species dependent upon the wetlands include American bitterns, Woodhouse’s toads, and white-faced ibis. Note that some wetlands are subject to seasonal closures to protect nesting waterbirds - watch for signs indicating closures.

    Because seasonal flooding no longer naturally replenishes the wetlands along the Green River, the Refuge staff pumps water from the river into these areas. Water is also diverted from Beaver and Vermillion Creeks. These water diversions create 1,755 acres of wetlands. Surrounded by arid, semi-desert uplands, the Refuge and the adjacent State of Utah’s Waterfowl Management Area contain the only significant wetland habitat for many miles around.

  • Grassland Habitat

     Nearly 1,700 acres of the Refuge are covered by grassland plants such as alkali sacaton, inland saltgrass, western wheatgrass, and Great Basin wild rye. These plants provide nesting cover for waterfowl, northern harriers, and songbirds such as the savannah sparrow. The grasslands also provide habitat for small mammals, like the montane vole, and crucial winter range for elk and mule deer. Over time, vegetation in the grasslands becomes heavily matted, and its habitat value decreases. The Refuge staff uses prescribed fire to remove the matted vegetation which restores the grassland habitat.

  • Upland Habitat

    Semi-desert shrubland dominates the upland habitat. Approximately 7,612 acres of semi-desert shrubland exists on the Refuge. The dominant plant species are shadescale, Wyoming big sagebrush, greasewood, needle and thread grass, and the non-native, invasive cheatgrass. Refuge species that rely on the semi-desert shrubland for breeding include sage grouse, Brewer’s sparrow, loggerhead shrike, Ord’s kangaroo rat, and sagebrush vole. The shrubland also provides winter range for mule deer, elk, and, to a lesser extent, pronghorn.

    The upland habitat also consists of about 1,083 acres of pinyon pine and Utah juniper, as well as interspersed areas of exposed rock along the southern boundary of the Refuge. Many species depend on this arid environment away from the river, including gray flycatchers, pinyon jays, several species of bats, and lizards.

  • Habitat Management Tools

     In their continuing effort to enhance Refuge habitats, the Refuge staff use a variety of management tools, such as prescribed fire, native plant seeding, big game hunting, and control of invasive weeds. On thousands of acres, invasive plant species, such as perennial pepperweed, cheatgrass, tamarisk, and Canada thistle, have become dominant, greatly reducing the value of the habitat available to wildlife on the Refuge. Biological, mechanical, and chemical controls are used to manage these invasive plants.