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8 Habitat Management and Rehabilitation
Pages 204-225

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From page 204...
... Restoration strategies for improving habitats are not always clear, and there is often disagreement among professional biologists, other technical specialists, land-managers, policymakers, and the general public regarding how to proceed. Programs to restore aquatic habitats have increased in recent years as the extent and magnitude of impacts of management activities and cultural practices on wetlands, streams, rivers, and estuaries have become more widely recognized.
From page 205...
... Reducing sedimentation is often another prerequisite for restoring aquatic habitats. In some instances, the transport of sediment to downstream reaches can be hindered or prevented.
From page 206...
... Because streamside vegetation has such an important influence on the characteristics and productivity of aquatic habitats, restoration of these habitats requires a commitment to the restoration of riparian vegetation functions and processes where they have been substantially altered by human influences. HABITAT-MANAGEMENT OPTIONS The influx of Euro-Americans has altered the characteristics and functioning of stream systems in most freshwater salmon habitats in the Pacific Northwest.
From page 207...
... to U} o _ ~ ~ ._ .O ~ ~ ._ = ~ ~ AS .m Cal Q ._ 1 Cal ._ Cal Cal ~ ~n o E ._ ~ ~ an tn 0 ~ C.) ~ , FIGURE 8-1 Alternative approaches to habitat management based on existing watershed conditions and desired level of improvement.
From page 208...
... s hydrology and sediment production, the prognosis for long-term re-establishment of a natural disturbance regime would be good. In other instances, natural hydrological and sediment-production processes have been not been impaired, but npanan vegetation and channel structure have been changed, and the recovery of riparian vegetation to a more natural condition might be the management goal (Table 8-13.
From page 209...
... Mitigation 1) Inventory riparian and aquatic habitat characteristics throughout watersheds.
From page 210...
... addition of large woody debris in configurations normally expected for the stream might be undertaken. In other instances, if riparian areas have been used for crop production, eliminating agricultural practices might initiate natural recovery of riparian functions and aquatic habitat; but because native plant species that would be characteristic of the local riparian system are infrequent, natural restoration could take a very long time, so planting native species of riparian plants obtained from locally adapted genetic stock might accelerate recovery.
From page 211...
... Natural disturbance regimes might have been altered to such an extent that there is little opportunity for restoration. For example, hydrologic and sediment transport regimes could have been affected by dams, irrigation diversions, changes in fire frequency, conversion of lands to agricultural practices, etc.; introduced plants could have replaced native riparian species; channel incision could have lowered local groundwater tables and affected hyporheic interchanges with the stream; estuaries could have been filled; and road construction, agricultural practices, or urban development could have reconfigured channel sinuosity or shifted stream location.
From page 212...
... For example, fully spanning logs with bank revetments might be placed in a stream that is deficient in pools to provide additional pool habitat. If the new pools are without cover and losses to predation are increased, if the logs create waterfalls that become barriers to juvenile or adult fish movements, or if the channel can no longer adjust to high flows and sediment transport by altering sinuosity or creating natural pools, the long-term consequences of the enhancement project might simply be another form of habitat degradation.
From page 213...
... Thus, there is an increasing need to understand cumulative effects not only on a sitespecific basis, but also across entire watersheds. Only through a broad geographic perspective can the unique qualities of each watershed and their spatial and temporal effects on aquatic habitats be effectively understood.
From page 214...
... The procedure was created in the Timber, Fish, and Wildlife Program in Washington State to address the cumulative effects of logging-related activities and has been incorporated into the state's forest-practices laws (Washington Forest Practices Board 1993J. Idaho is developing a cumulative-effects analysis and control process designed to protect water quality from forested watersheds so that beneficial uses are supported (Idaho Department of Lands 19941.
From page 215...
... Spatial context. The highly varied nature of fish habitat requires that geomorphic characteristics of aquatic habitats be identified throughout a basin.
From page 216...
... It is important for both society and fishery managers to understand the magnitude and extent of changes that have occurred over periods of decades or longer. Watershed analysis requires gathering a large amount of inventory information to obtain an improved understanding of how spatial and temporal patterns, cause-effect relationships and other interactions, and cumulative effects occur in a particular watershed or stream reach and how they affect aquatic habitats.
From page 217...
... Similar institutional constraints occur with respect to other resources and land-management practices. Unless the role and importance of various social, economic, institutional, and population factors that affect aquatic habitats are considered, the potential for effective maintenance or improvement of habitat for anadromous salmon and other aquatic organisms will be greatly constrained.
From page 218...
... Nevertheless, degraded aquatic habitats can be improved in large portions of the Northwest's stream systems. Most of the length of a stream network comprises relatively small streams, which provide water, nutrients, organic matter, and sediment to downstream reaches.
From page 219...
... Attempts at improving habitats by adding in-channel roughness elements without eliminating management practices that are causing habitat degradation are likely to fail. For example, some short-term habitat benefits might be achieved by adding large woody debris to streams, but the benefit can be only temporary from an ecological perspective unless riparian management practices ensure the long-term recruitment of large woody debris from the riparian zone.
From page 220...
... 1993, FEMAT 19933. Because naturally functioning riparian ecosystems are crucial to sustainable and productive aquatic habitats, riparian plant communities along stream channels are often protected by setting a specific distance from the channel within which anthropogenic disturbances are minimized or excluded.
From page 221...
... as an appropriate habitat-conservation measure for endangered salmon in the Snake River basin. If applied to privately owned forests inhabited by salmon, the system of large buffer strips recommended by FEMAT (1993)
From page 222...
... The committee believes that providing greater consistency in protecting aquatic habitat on private lands should have high priority in state and local governments. A second means of improving habitat protection on privately owned lands is to involve property-owners more fully in environmental-policy matters so that
From page 223...
... A few local property owners practicing improved habitat conservation can act as examples and catalysts for others. On the watershed or river-basin scale, private landowners can participate in joint planning organizations that help to set environmental policy and promote environmental stewardship.
From page 224...
... But simple habitat features can be monitored by lay persons, and public participation can be a powerful tool not only for expanding habitat databases but also for environmental education. A better-educated public is far more likely to recognize the longterm value of protecting aquatic resources through individual actions that promote environmental stewardship than a public that tends to lay the problem at someone else's doorstep.
From page 225...
... HABITAT MANAGEMENT AND FISHERIES MANAGEMENT There is critical interaction between habitat management and fisheries management. Many habitat alterations do not directly extirpate populations, but instead reduce survival rates so as to reduce sustainable exploitation rates.


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