Located within a nationally-designated Wild and Scenic River Corridor and wilderness portal, Deadwater Slough has scenic and recreational values enjoyed by thousands of visitors each year. Its natural, pastoral setting and slack waters are a visually beautiful and desirable setting for a number of recreational activities. The site is also an excellent wildlife viewing spot, featured in The Birds of East Central Idaho, Idaho Wildlife Viewing Guide, and A Birder?s Guide to Idaho.
Deadwater Slough is a 3-mile complex of riparian floodplain and forest, grass meadows, braided stream channels, islands, and backwater sloughs along the Salmon River. As its name suggests, Deadwater Slough is located in a river reach of gentle gradient which supports one of the highest quality cottonwood gallery forests in east-central Idaho. There are few, if any other sites in the Upper Salmon Basin that have the comparable uniqueness of such a large, broad floodplain complex with extensive sloughs and cottonwood gallery forest.
Deadwater Slough is one of east-central Idaho?s best birding locations due to quality riparian habitat, good water quality, adjacent proximity of diverse upland habitats, and lack of disturbance. Within the Intermountain West Avifaunal Biome (and especially in arid east-central Idaho), riparian areas such as Deadwater Slough comprise a relatively small percentage of the land base, and thus support a high concentration and diversity of bird life. The unique hydrology of the site, including slow to fast water velocities, offers habitat for a wide variety of water-associated birdlife.
The first contemporary record of nesting bald eagles in east-central Idaho (Idaho Recovery Zone 15E) was at Deadwater Slough in 1990. This territory has been continuously occupied for 16 years (through 2005), producing 19 fledglings. This territory is considered a key contributor to the expansion of the breeding bald eagle population in Idaho Zone 15E.
Deadwater Slough is also an important breeding habitat for several Bird Conservation Region (BCR) 10 Species of Continental Importance and Idaho Species of Special Conservation Need: Lewis?s Woodpecker, Willow Flycatcher, Yellow Warbler, McGillivray?s Warbler, and Brewer?s Sparrow. Other BCR 10 Watch List and Stewardship species found in the Deadwater vicinity (i.e., adjacent uplands) are Rufous Hummingbird, Calliope Hummingbird, Green-tailed Towhee, Clark?s Nutcracker, and Mountain Bluebird. The cottonwood forest provides abundant nesting/foraging substrate for many primary and secondary cavity-nesting birds such as Wood Duck, American Kestrel, Pileated Woodpecker, and Hooded Merganser.
The nominated site is also used as a migratory stopover for waterbirds and waterfowl including Common Loon, Western Grebe, Red-breasted Merganser, Snow Geese, American Widgeon, Redhead, Ring-necked Duck, Bufflehead, and an occasional Trumpeter Swan.
The following birds have been documented at Deadwater Slough by local, experienced birders: Canada goose, American Wigeon, Mallard, Blue-winged Teal, Cinnamon Teal, Northern Shoveler, Northern Pintail, Common Merganser, Chukar, Ruffed Grouse, Blue Grouse, Gambel?s Quail, Pied-billed Grebe, Great Blue Heron, Osprey, Sharp-shinned Hawk, Red-tailed Hawk, Golden Eagle, Northern Pygmy Owl, Sora, Killdeer, Spotted Sandpiper, Wilson?s Snipe, Wilson?s Phalarope, Mourning Dove, Great-horned Owl, Common Nighthawk, Belted Kingfisher, Downy Woodpecker, Hairy Woodpecker, Northern Flicker, Western Wood-Pewee, Say?s Phoebe, Eastern Kingbird, Warbling Vireo, Red-eyed Vireo, Black-billed Magpie, American Crow, Tree Swallow, Violet-green Swallow, Northern Rough-winged Swallow, Black-capped Chickadee, Red-breasted Nuthatch, Canyon Wren, Rock Wren, House Wren, American Dipper, Ruby-crowned Kinglet, Mountain Bluebird, Townsend?s Solitaire, American Robin, Gray Catbird, Nashville Warbler, Yellow-breasted Chat, Spotted Towhee, Lark Sparrow, Song Sparrow, Dark-eyed Junco, Black-headed Grosbeak, Lazuli Bunting, Red-winged Blackbird, Western Meadowlark, Bullock?s Oriole, Pine Siskin, and Evening Grosbeak.
Management of noxious weeds, including leafy spurge (Euphorbia esula), spotted knapweed (Centaurea maculosa), yellow toadflax (Linaria vulgaris), and Canada thistle (Cirsium arvense), is the primary conservation concern at Deadwater Slough. Leafy spurge and spotted knapweed infestations have been associated with reductions in forage production, plant species richness and diversity, cryptogam cover, soil fertility, and wildlife habitat, as well as increases in bare ground, surface water runoff, and stream sedimentation. Adjacent range and forest lands, both public and private, contain large-scale knapweed infestations that could potentially spread to Deadwater Slough. The North Fork Ranger District of Salmon-Challis National Forest has implemented an aggressive integrated weed management program to control infestations. However, Deadwater Slough is probably less susceptible to colonization due to its healthy vegetative/ecological condition and absence of soil disturbing activities (i.e., roads, trails, motorized travel, and livestock grazing).
On adjacent forested slopes, fire exclusion has led to an in-growth of smaller conifers that has predisposed these densely-stocked stands to lethal fire and attack from insects. Wildfire under such heavy fuel conditions may potentially spread and consume riparian habitat in Deadwater Slough.
Located within a nationally-designated Wild and Scenic River Corridor and wilderness portal, Deadwater Slough has scenic and recreational values enjoyed by thousands of visitors each year. Its natural, pastoral setting and slack waters are a visually beautiful and desirable setting for a number of recreational activities. Seasonal float boating, whitewater rafting, steelhead fishing, and hunting are some of the most popular recreational opportunities, supplying important tourism dollars to local economies. The site is also an excellent wildlife viewing spot, featured in The Birds of East Central Idaho, Idaho Wildlife Viewing Guide, and A Birder?s Guide to Idaho. The site has also been nominated as an Idaho Birding Trail portal site. Deadwater Picnic Area is a free picnic and boat launch area with toilets and picnic tables. Fishing, swimming and rafting opportunities are available at the site.
The Lewis & Clark Expedition navigated through Deadwater Slough in 1805 hoping to find their elusive route to the Pacific. Instead, just below Deadwater, the party came to a ?dreadful narrows? where the river was so confined by the mountains, passage was impossible, hence the origin of ?River of No Return.? Prehistorically, the Salmon River corridor was occupied by Native Americans of the Shoshone culture. Archaeological excavations a few miles downriver from Deadwater located Native American cultural components dating to 8,000 years ago. The Salmon River reach including Deadwater is of exceptional importance for interpreting prehistory.