This wildlife management area includes large tracts of undisturbed wetlands along the lower Coeur d?Alene River and portions of the shoreline and adjacent wetlands for several lakes.
There are numerous lakes, rivers, and creeks throughout the CDARWMA. Peripheral to these areas are also numerous wetlands that support a variety of wildlife, including high densities of waterfowl. Water in this area is managed primarily for recreation, flood control, and aesthetic purposes. The CDARWMA was acquired primarily for its waterfowl production values and as such, most monitoring of waterfowl populations occurs in this area of the district. Monitoring of duck and geese populations is emphasized as a means to evaluate habitat quality and management.
The CDARWMA is valuable to many bird species, but particularly to waterfowl because of its abundant wetland habitat. Shorebirds also use the lakes and adjacent wetlands when water levels drop and mud flats and floating bogs are exposed. Tundra swans are abundant during migration, as well as numerous diving and dabbling ducks. Other waterbird species of interest include common loons, red-necked, western, and Clark?s grebes, American white pelicans, and Caspian terns which all use the WMA for a portion of the year.
Upland habitat is limited on the WMA but does support Lewis? woodpecker, possibly flammulated owl, and short-eared owl.
Effects of mining for precious metals in the 1800s are still felt today throughout the lower Coeur d?Alene River Valley. Lead levels in soils have been documented between 500 and 10,000 ppm, in contrast to the national baseline average of 8-25 ppm. Impacts to waterfowl are most widely-studied and lead-related mortalities to swans, ducks, and geese are not uncommon. It should be noted, however, that despite the contamination and resulting mortality, productivity on the WMA greatly exceeds mortality caused by contaminated soils. As such, this area would not be regarded as a population ?sink?. Remediation efforts to clean up toxic levels of heavy metals are guided by the EPA, which has classified the lower Coeur d?Alene River Valley and Lake Coeur d?Alene as a superfund site. Various clean up efforts have been proposed or are underway.
Water is managed primarily for recreation, flood control, and aesthetic purposes. Local watersheds are all impacted by water levels in dam-controlled Lake Coeur d?Alene. Every year, water levels in the Lake drop in fall, remain low through winter, and rise in spring and summer. This has a direct impact on shoreline nesting birds who establish nests in spring only to have them flooded as summer progresses. Combined with the above management actions, wakes from recreational boaters cause significant erosion to banks of the Coeur d?Alene River. Because water level management impedes growth of stabilizing vegetation, bank stabilization to preserve riparian habitats, private property, and to reduce transport of contaminated soils downstream, will continue to be a management challenge. Bank stabilization projects are proposed for portions of the Coeur d?Alene River.
Invasive species, such as the American bullfrog, canary reed grass, and various noxious weeds are a management problem. While invasive plants are actively addressed, little effort has been made to assess or address the problem of a growing bullfrog population
Dominant plant species include canary reed grass (Phalaris arundinacae), steeplebush (Spiraea douglasii), wild rice where it has been planted by humans, Carex spp., Juncas spp, cottonwood (Populus spp.), birch ( Betula spp.), aspen (P. tremuloides), cattail (Typha latifolia), and Fragmides spp. (introduced for soil stabilization). Wild rice is common throughout the WMA and provides and important food source for migrating and nesting waterfowl. Upland sites are a mix of ponderosa pine (P. ponderosa), Douglas fir (P. menzezii), grand fir (A. grandis), and lodgepole (P.contorta). One parcel near Thompson Lake includes ponderosa pine that are over 100 years old.
Soils vary from shallow rocky soils on upland sites to seasonally flooded wetland soils and floating bogs. Water levels are heavily managed at the Spokane River Outlet dam on Lake Coeur d?Alene and the effects of this management can be seen throughout the WMA all the way upstream to Cataldo. Precipitation in Fall and Winter cause water levels to rise, but releases of dam water cause them to quickly drop again. Water is released in the winter to make room for spring runoff. By early spring water releases result in very low levels, and lots of exposed shoreline. But as runoff increases, water levels rise, flooding these areas. By the end of summer, drier weather conditions bring water levels back down.
Geology of the area is dominated by the activities of the Coeur d?Alene River, its movement of soil, and the sedimentary rock that ultimately is deposited. Upland sites are dominated by basalt rock that is often columnar in appearance.
The most significant economic value of the WMA is recreational in nature. Over 18,000 visitor use days were documented on the WMA in 2005, most of this was related to fishing, hunting and trapping. But the construction of the 72-mile long ?Trail of the Coeur d?Alene? recreation bike path has resulted in a huge influx of visitors to the Valley. Over 100,000 people accessed the Trail last year. This addition of tourism to the scene has had great impacts on local service economies, at least on a seasonal basis. Other economic values include agricultural uses (livestock and hay production), and timber and mineral uses also dominate the local economy. Social values include the long rural history of logging (old mill sites, log drives etc.) and mining. Local people are fiercely protective of their pastoral setting and many resent the recent influx of tourism.