Monitoring

Monitoring and evaluation are fundamental components of aquatic habitat management in the Pacific Northwest Region, providing information and feedback to improve activities in resource protection and restoration programs.

Monitoring efforts vary considerably, depending on the specific questions to be answered, such as implementation and effectiveness of activities or programs, or portraying general trends in resource conditions. Monitoring efforts also vary widely in scope and scale, from individual project reaches, to stream systems, watershed-wide, provincial and regional.

An example at the larger, sub-regional scale is the Aquatic and Riparian Effectiveness Monitoring Plan (AREMP), intended to characterize the ecological condition of watersheds and aquatic ecosystems in the area covered by the Northwest Forest Plan (western Oregon and Washington.) It will determine existing watershed condition based on upslope, riparian, and in-channel attributes, track trends in watershed condition over time, and report on the Forest Plan's effectiveness across the region. AREMP will also supply information that will be useful in determining causal relationships to help explain those trends.

Over a five-year period, a total of 250 watersheds will be sampled (approximately 10% of the estimated total number). Watershed condition will be analyzed using indicator values in a decision support model (DSM), incorporating relationships developed by provincial and regional experts. Results will be presented in the form of frequency distributions of the regional aggregation of watershed condition.

Another example of effectiveness monitoring at the local, project scale is evaluation of fish habitat and population response to channel reconstruction in Enchanted Valley, Siuslaw National Forest. Two seasons following construction, a five-fold increase in juvenile fish use has been observed in this project area. Monitoring of improvements in and around Applegate Lake (.pdf, 1.2mb) has focused on evaluation of habitat and recreational improvements, and has shown that: 1) 10-15% of anglers are utilizing access improvements at the lake; 2) juvenile bass populations have increased while adult number remained stable; and 3) survival of riparian plantings can be improved through changes in planting techniques.

A final example of effectiveness monitoring (at the National Forest scale) is an evaluation of in-stream structures placed in several streams on the Umatilla National Forest (see Umatilla Structure Evaluation (.pdf, 1.8mb)). The study showed increases in such variables as pool number and depth in half the treated reaches, and most reaches were shown to have met target values for deep pools (greater than 2 feet) per wetted width of stream.

Enchanted Valley Stream Restoration

The Oregon Coast Range was once a prime production area for coho salmon (Oncorhynchus kisutch). Sadly, today much of the freshwater habitat for silver salmon, another name for coho, has been altered to the point that it is no longer suitable for spawning and early rearing of these magnificent fish. It seems that coho prefer much of the same areas as humans do, namely lush, low-gradient stream valleys with wide flood planes. Beginning in the late 1800's Euro-American settlers began converting these low gradient stream valleys to farmland. In the process the slow, meandering streams in these valleys were straightened and diked to prevent damage from floods. The straightened channels increased the stream's velocity and provided few resting places for young coho salmon. Bailey Creek, flowing through Enchanted Valley just north of Florence, Oregon is just one example of this, but is an example with a happy ending.

Enchanted Valley was acquired by the Siuslaw National Forest through a land exchange in 1991. The valley floor had long ago been converted to pasture to make way for a dairy farm. Initially, the Forest Service planned to maintain the open nature of the pasture to benefit elk, but its potential as salmon habitat soon became apparent. The photo, below, shows Enchanted Valley as it appeared in 1955. Bailey Creek has been channelized for the entire length of the valley. A remnant of the old channel is still visible as a meandering thread in the upper 2/3 of the valley. By the time the Forest Service acquired the valley even this remnant channel was gone.

Restoration - The primary purpose of the restoration project was to improve rearing conditions for juvenile coho salmon by recreating a meandering channel through the middle of the valley. In order to accomplish this, a whole new channel for Bailey Creek had to be constructed. This was done using heavy equipment including excavators and dump trucks. Because of concerns for elk habitat, and because this approach to restoration is somewhat new, only the lower 1/3 of Enchanted Valley was treated. The project was implemented in 1999 and 2000, with some additional work occurring in 2001. Monitoring of the success or failure of the project will determine if the remaining portion of the valley will be treated in the future.

The photos below show the lower 1/3 of the valley before and after channel construction. Note the sinuous nature of the new channel. The old channel ran along the right margin of the valley. Erosion in the old channel created the delta extending into Mercer Lake shown in the lower portion of the photo.

Before	After

Monitoring the Results - Monitoring of the Enchanted Valley Stream Restoration project is very important to demonstrate success or failure of the project. A wide-array of parameters are monitored including channel movement, erosion, turbidity, delta formation, pool volume (juvenile coho habitat), and coho numbers. Preliminary results are discussed below.

Potential for erosion and migration of the newly created stream channel was a major concern of project implementers. To keep track of the rates of erosion and migration 24 cross-section surveys and 48 photo points were created. The photos below are from just one of these photo points and demonstrate the rapid recovery of streambank vegetation and aquatic plants. Willows planted along the banks should eventually provide shade to the stream.

Because young coho salmon prefer slower moving water, the amount of pools present in the new channel was closely monitored and compared to the old channel. The sinuous nature of the new channel increased total channel length by 30% over the straightened old channel, however, pool volume increased by an even bigger amount - a 100% increase. Juvenile coho abundance was also monitored and showed even more impressive results. Because the year 2000 saw very good returns of adult coho to Oregon coastal streams, numbers of juvenile salmon rearing in the new channel must be compared to the numbers that used to rear in the old channel and to numbers in a section of stream used as a control. First year results show a five-fold increase in juvenile coho salmon using the new channel when compared to numbers estimated for the old channel!