Biologically Unique Landscapes
The Nebraska Natural Legacy Project: State Wildlife Action Plan identifies landscapes based on known occurrences of natural communities and at-risk species and sets goals for each community type and certain at-risk species (Schneider et al. 2011).
A set of landscapes were determined that offer some of the best opportunities for conserving the full array of biological diversity in Nebraska. Thirty-nine landscapes across the state were considered to be some of the last strongholds in Nebraska for many species and were, therefore, designated Biologically Unique Landscapes (BULs). The Plan has a description of the landscapes, a list of the species at-risk of extinction or extirpation from the state, and an outline of conservation strategies for each of the BULs.
Middle Niobrara River BUL
A stretch of this BUL located in Cherry, Keya Paha and Brown counties has been designated as a National Wild and Scenic River due to its unique natural resource values. The Niobrara River valley in this reach is often referred to as the Biological Crossroads of the Midwest due to its diversity of plant communities and unique array of plant and animal species they support.
The Middle Niobrara BUL supports multiple at-risk species, some of which are threatened or endangered. The Nature Conservancy's Niobrara Valley Preserve alone supports 581 plants species, 213 birds, 86 lichens, 44 mammals, 25 fishes, 17 reptiles, and 8 amphibians. Other conservation lands within the BUL include Fort Niobrara National Wildlife Refuge, Smith Falls State Park, and several state wildlife management areas and state recreation areas.
Oglala Grasslands BUL
This area supports a unique array of high-quality plant communities including northwestern mixed-grass prairie, threadleaf sedge western mixed-grass prairie, silver sagebrush shrub prairie, greasewood shrub prairie, badlands, rock outcrops, spikerush vernal pool, among others.
This BUL also supports populations of four Tier 1 at-risk plant species including Barr's milkvetch (Astragalus barrii), dog-parsley (Lomatium nuttallii), Gordon's wild buckwheat (Eriogonum gordonii), and Rocky Mountain bulrush (Schoenoplectus saximontanus). The area is also an important nesting area for ferruginous hawk (Buteo regalis) and chestnut-collared longspurs (Calcarius ornatus) and an important foraging area for golden eagles (Aquila chrysaetos) and prairie falcon (Falco mexicanus). The BUL is the location of the Oglala National Grasslands, which provides a large complex of conservation lands.
Saline Wetlands BUL
These rare wetlands provide habitat for a number of resident and migratory species. The state and federally endangered Salt Creek tiger beetle (Cicindela nevadica lincolniana), one of the world's rarest insects, is known to occur only in these saline wetlands. More than 200 species of migratory birds have been recorded using the wetlands. Saltwort (Salicornia rubra), an endangered plant species in Nebraska, is only found in these wetlands and represent the southernmost permanent extant of the species. Once expansive enough to consider as for a salt mining operation, many of these wetlands have been lost due to urban expansion and agricultural activities.
Sandhills Alkaline Lakes BUL
This is a highly pristine area of the Nebraska Sandhills containing a mix of upland prairie communities and both alkaline and freshwater wetlands. The uplands contain both sandhills dune prairie and sandhills dry valley prairie (G3/S4), as well as wetland types including western alkaline marsh, western alkaline meadow (G3/S3), reed marsh, northern pondweed aquatic wetland, among others.
The region also supports some of the largest populations of the federally and state endangered blowout penstemon (Penstemon haydenii). This species occupies open sand blowouts on dune tops, which would be highly susceptible to wind development. Wetlands in this BUL are critical for migratory and breeding shorebirds and waterfowl.
Upper Niobrara River BUL
This rugged upper Niobrara River valley supports a diverse array of near-pristine plant communities. Uplands support several mixed-grass prairie communities and extensive rock outcrops. The river bottoms support some of our state's most extensive examples of western subirrigated alkaline meadow, a G3/S2 plant community, among other wetland types.
This BUL supports populations of four Tier 1 at-risk species: Gordon's wild buckwheat, large-spike prairie-clover (Dalea cylindriceps), meadow lousewort (Pedicularis crenulata), and the state's only population of the state and federally threatened Ute lady's-tresses (Spiranthes diluvialis). The upper Niobrara River valley is one of the state's most important raptor nesting areas.
Wildcat Hills BUL
Despite the area's small size it has some of the greatest plant diversity in the state. The escarpments contain a diverse mosaic of high-quality plant communities ranging from pine woodlands and forests (G3G4/S3S4), mountain mahogany shrublands, western sedge meadow, threadleaf sedge western mixed-grass prairie, sandsage prairie, badlands, and rock outcrops, among others.
The occurrences of mountain mahogany shrublands are by far the most extensive in the state. Extensive portions of the Wildcat Hills (over 20,000 acres) are under conservation ownership, making the region even more valuable for biodiversity conservation. The Wildcat Hills are one of the state's most important areas for nesting raptors, including golden eagles. The state's most stable population of bighorn sheep (Ovis canadensis) is also found here. The Wildcat Hills and the Pine Ridge have been identified as priority landscapes for fringed myotis (Myotis thysanodes), a G2 subspecies and Tier 1 bat species.
How this map was used: Most BULs were classified as Medium Relative Sensitivity and Moderate Mitigation Areas. The six BULs discussed above were classified as High Relative Sensitivity and Maximum Mitigation Areas based on their importance to biodiversity, high percentage of intact native landscapes, and other variables.