North Cascades National Park has adopted a watershed approach to long-term ecological monitoring beginning with watershed analysis as described in the Northwest Forest Plan. The watershed approach tracks upslope processes and conditions, but places an emphasis and enhanced resolution on aquatic and riparian habitat and communities. This approach will allow us to extrapolate site-specific information from lakes, ponds, wetlands, or stream reaches to watersheds, river basins, and landscapes. Most watersheds in the North Cascades NP drain into the Skagit River basin on the west slope of the North Cascades Range and the Stehekin River on the east slope. They are unaltered by past human-induced disturbance and can serve as reference sites and templates for restoration efforts in the Pacific Northwest.

The condition of a watershed is the reflection of the distribution and types of seral classes of vegetation, land-use history, effects of previous natural and cultural disturbances, and the distribution and abundance of species. Major natural disturbances affecting the mountainous regions in the Pacific Northwest are episodic floods, volcanic eruptions, earthquakes, geomorphic changes in stream channels and landforms, fire, wind, insect and disease outbreaks, and glacial activity. Important landform disturbances include landslides and earthflows in glacial deposits on steep slopes.

Human-induced disturbances include alterations of water quality and quantity, habitat destruction or modification, and biological impacts such as the invasion of non-native plants or animals, fish harvesting or stocking, road construction or intrusive maintenance, deposition of air pollutants such as pesticides and heavy metals, and the introduction of non-native diseases. These disturbances may reduce or eliminate key ecosystem components or processes and reduce the efficiency of nutrient cycling, change productivity, alter species diversity, change size/age distribution and faunal life-history traits, increase isolation, and alter the incidence of disease.

Watersheds have distinct physical boundaries and define the ranges of plants and animals. They integrate climatic, geologic, hydrologic, and biotic components in the alteration of habitat as vast quantities of water and sediment move from source areas in high mountains to low-elevation valley floors. Watershed analysis methods provide a framework for understanding ecological processes at various scales. Big Beaver Creek, Thunder Creek, and Bridge Creek are "target watersheds" for pilot studies in the context of the Long-Term Ecological Monitoring (LTEM) program. These watersheds were selected based on patterns of climate, geology, hydrology, biology, accessibility, and linkages to management concerns.

Big Beaver Creek flows easterly into Ross Lake reservoir, so there is a strong linkage to the Seattle City Light hydroelectric project. The valley floor is covered with lush riparian and wetland vegetation that is part of a Research Natural Area. This watershed is 16,780 ha in size, and has 174 km of streams, 12 glaciers, and 43 lakes. It is situated within a climatic transition zone between the cool, wet climate of the west slope and the warmer, drier east slope. Thunder Creek is the largest watershed at 31,430 ha. It has 315 km of streams, 51 glaciers, and 28 lakes. It too is located in the climatic transition zone, but with a much greater west slope influence. Bridge Creek is an east slope watershed with a mountainous ridgeline separating it from Thunder Creek. It is 23,360 ha in size and has 288 km of streams, 25 glaciers, and 34 lakes.

As we conduct surveys and learn more about these watersheds, we are also considering other watersheds for inclusion in the LTEM program. The Stehekin River is eligible for Wild and Scenic River status, but has challenging management issues because of adjacent roads, private property, and fish stocking in Lake Chelan. The Goodell Creek watershed was logged before the establishment of the Complex, and is recovering, but it would provide the LTEM program with a watershed having salmon and steelhead runs from the Skagit River. Finally, we have been assessing the resources of the Chilliwack River in cooperation with other agencies since 1998 (see below).

Watershed restoration is a major public issue and land management objective in western North America. The Chilliwack River watershed is a prime international example, and may be considered for the LTEM program in the future. In the United States (National Park Service), it has been managed as designated Wilderness and under the U.S. Northwest Forest Plan it is a Tier 1 Key Watershed in the Aquatic Conservation Strategy. In Canada, it has been managed for multiple consumptive resource use with logging, road building, recreation, fish hatcheries, and other activities. The Chilliwack River originates in the United States and flows northwest into the Fraser River south of Chilliwack, British Columbia. The watershed is 31,350 ha in size with an elevation range of 550-1,740 m. The Chilliwack River has significant anadromous salmon populations (sockeye, coho, steelhead, and chinook), as well as resident fish populations, including bull trout, rainbow trout, cutthroat trout, and mountain whitefish.

The USDA Forest Service (Mt. Baker-Snoqualmie National Forest), National Park Service (North Cascades National Park), Province of British Columbia (Ministry of Lands, Parks, and Environment), and the University of British Columbia are cooperating to inventory and monitor the upper Chilliwack River. This portion of the watershed can serve as a reference site or template for future restoration work elsewhere in the Pacific Northwest. To date, they have conducted Level II and III watershed surveys of its physical, chemical, and aquatic biological resources.

Other disciplinary work includes archeological surveys in the subalpine and alpine zones, and mapping past fire patterns in the watershed to improve our perspectives on human use, time frames, and disturbance events. Native American artifacts have been traced to nine obsidian outcrops and indicate use for thousands of years. Charcoal from subalpine archeological sites established the first high elevation chronology of pre-contact indigenous use from 4,500 years BP. In 1859, working for the U.S. Boundary Commission, Henry Custer conducted the first extensive non-Indian explorations of the subalpine and alpine habitats of the Pacific Northwest, and found the Coast Salish people able to prepare simple, but accurate maps of the Chilliwack River watershed.

The diversity of watersheds from west to east across the North Cascades National Park Service Complex provide a framework for long-term monitoring, as well as other research efforts and analyses. By focusing on a few watersheds, we will have sufficient resolution to quantify environmental change and will have the scientific foundation to provide input to resource management decisions.