Some of the declining populations of naturally spawning salmon are at such low levels (e.g., spring chinook of the upper Grande Ronde River) that they may be extirpated before passive habitat restoration efforts yield significant benefits. Passive restoration involves curtailing or deferring activities that contribute to habitat degradation or forestall recovery. It is brought about by management that establishes riparian and roadless reserves and controls watershed-wide sediment delivery to streams to a level considered capable of allowing the stream channels to cleanse themselves of fine sediment, reestablish pools and channel morphology, and reduce embeddedness.
Active habitat restoration may be required in cases where watershed or stream restoration would not occur via natural processes for prolonged periods. However, past active restoration efforts (e.g., revegetating streambanks, providing instream structures, and obliterating roads) have frequently failed because of impacts (e.g., increased peak flows, sediment loads, and water temperatures) from cumulative actions elsewhere in the watershed (Beschta et al. 1991; Kauffman et al. 1993). Provided that land use standards are uniformly and consistently applied as described in Rhodes et al. (1994), including application of passive restoration techniques on a watershed basis, active watershed and riparian restoration (especially riparian planting of native vegetation, fencing, and road obliteration) will be an essential part of land management and restoration of in-channel habitat conditions.
Active habitat restoration is needed to maintain and increase productivity of some of the naturally spawning salmon populations in areas where habitat is most damaged (e.g., many portions of the Yakima, Grande Ronde, Umatilla, and John Day Rivers). When it is part of a comprehensive watershed-based program that addresses cumulative impacts to in-channel habitat condition throughout salmon-bearing stream systems, active habitat restoration will increase egg-to-smolt survival, increase the productive capacity of watersheds for salmon and lamprey, and help halt present declines in these populations. Volume II describes many active restoration measures needed in subbasins above Bonneville Dam.
Implement active restoration measures identified in the Subbasin Plans. Develop a tribal watershed restoration trust fund to fund restoration actions and provide active coordination and participation in watershed restoration activities through the provision of no less than 1 FTE in each watershed. Ensure tribal participation and technical participation from the tribes in ongoing community based watershed councils to coordinate and implement watershed restoration actions. Organize community based watershed councils where appropriate.
Develop, in cooperation with existing programs (e.g., Salmon Corps), active restoration projects in the Grande Ronde, John Day, and Yakima Rivers. Use, where appropriate, the Coarse Screening Process guidelines (Rhodes et al. 1994) (Tables 5B.2 and 5B.3) and other techniques to:
- Assist in the preservation and restoration of salmon populations identified as Badly Damaged and Declining by CRITFC (1992),
- Reconnect fragmented habitat for Badly Damaged and Declining populations,
- Address other problems identified in Subbasin Plans, thereby restoring watershed-wide stream system integrity and improving chances for successful reintroduction to areas of extirpated salmon.
Develop monitoring programs (baseline and trend, effectiveness, and validation at various geographic scales of resolution; see McCullough and Espinosa (1996) for discussion of necessary forms of monitoring) in association with restoration projects to document recovery trends in habitat condition and to further define relationships among land use, instream habitat condition, and salmon production. Use community based watershed councils to develop volunteer monitoring programs to be used in conjunction with other scientific monitoring. These programs need to identify key land use-salmon production interactions, and effective ways to improve watershed conditions that degrade or impede habitat condition and decrease salmon production; be oriented toward application of measures known to be effective in promoting instream habitat recovery; and provide quantitative evaluation of the magnitude of improvement and rate of recovery of habitat quality and quantity, and associated benefits to salmon and lamprey survival and production.
Develop active habitat restoration and protection projects in additional watersheds as a part of ongoing and organizing community based watershed councils.
Continue monitoring programs as needed for the purposes described in the short term.
Short-term: Improvement in egg-to-smolt survival will be afforded some of the most threatened salmon populations (i.e., to those populations residing in watersheds selected as demonstration projects).
Long-term: Assistance in rebuilding both the most seriously threatened salmon populations (e.g., Badly Damaged and Decreasing as defined by CRITFC 1992a) and also those populations that may be stable but confined to low production levels as a result of poor habitat quality/quantity or fragmented habitat. This is a result of improvement in habitat quality and quantity and stream system integrity. Survival rates and population densities for salmon and lamprey will increase, and thus restore a degree of buffering against natural environmental fluctuations.
The watershed productivity for salmon and lamprey will increase, and natural communities and ecological functions will be restored by increasing the quantity of usable habitat. In addition, connections will be reestablished among sections of fragmented salmon habitat, thereby improving stream system integrity.
By intensive monitoring of various representative stream reaches, entire stream systems, riparian areas, and watershed conditions in salmon-bearing watersheds, models used by land managers will be improved to better assist in controlling impacts or predicting improvements from restoration actions.
The ability to prescribe active restoration measures (e.g., plant species for revegetation) from identification of limitations to habitat recovery (e.g., riparian soil or hydrologic conditions) on a site-specific scale will improve.
Federal, state, tribal land and fishery managers as well as counties, local governments, and private landowners will be responsible for developing cooperative arrangements for land and water management activities that will increase salmon productivity using appropriate techniques. Monitoring must be used to ensure actions will provide increased productivity and to understand the connectivity of actions within the Columbia River Watershed.