79 



Spotted Owl from the Cascade Mts. to the ocean (Northein Spotted Owl recovery Plan. Appendix D). Similar patterns 

 and levels of depletion can be found m arid and semi-arid biomes throughout the region. 



The economic and social impacts of degraded riverine systems and lost fisheries and biodiversity are severe. Just a few 

 examples are necessary to depict the impacts. Since 1910. annual salmon and steelhead runs of the Columbia nver 

 system have decUned from approxmiately 10-16 million to 2-2. S million. Yet. die fishery still produces over $1 billion a 

 year m income and supports 60,000 jobs regionwide (using 1988 figures). How many jobs and economic benefits could a 

 healthy fisber>' produce? Further, diminished and polluted water suppbes produced by die regions watersheds are 

 affecting irrigatioa and mumcipal water supplies and threaten public health. 



In short, almost every segment of society has been affected by and pays heavy direct and indirect ecological, fmancial. 

 and job-related costs for the degradation of the regions riverine systems, fisheries and riverine biodiversity, whether they 

 are aware of it or not. 



THE CAUSES OF THE PROBLEMS: Aldiough the media has generally focused the problems on mainstem Cohmibia 

 dams, these types of broad ranging problems cannot be blamed exclusively on dams, nor on excessive fishing, or on 

 predators such as sea Uons. Over 175 of the 214 at risk satanonids spawn outside of the Cohimbia basin, most in coastal 

 rivers unaffected by dams. Most of these species are not subject to commercial harvest. Poor ocean conditions, dams and 

 overharvest would not explain the vast number of r^Mrian species or resident fish such as Bull Trout ttiat are at risk. 



The cumulative degradation of watershed ecosystems and the loss of riverine habitat is the single most consistent 

 contributor to the decline of the region's fisheries and riverine biodivetsity. 



The cumulative result of the many human impacts on riverine systems has been called "ecosystem simplification': huge 

 reductioDs in the life-supporting complexity and diversity of watershed and riverine ecosystems and habitats. 



In brief, riverine ecosystem and habitat simplification relates to: 1) changes in water quantity or flow due to irrigatioa 

 and odier withdrawals, 2) the modification of channel and rq>arian ecosystem morphology caused by damming, 

 reservoirs, channelization, drainage and filling of wetlands, and dredging for navigation, 3) excessive nonpoint-source 

 poDutioa, inchiding erosion and sedimentation caused by damaging land-use practices, including agriculture, forestry, 

 and urbanizatioa. 4) flie deterioration of substrate quality or stability, S) the degradation of chemical water quality 

 through die addition of point-source contaminants, 6) the decline of native fish and other species from overharvest and 

 intentional or accidental poisoning, and, 7) the introductioD of exotic species. 



Loss of Physical habitat: Many scientists have linked the fiitiire of die region's native fishes directly to the changes in 

 the managemoit of federal forests and other lands across the region. Loss of physical complexity in lowland rivers which 

 primarily flow through private lands is extensive. Virtually all lowland rivers throughout the region have been 

 umversally degraded dirough channdizatioa, diking, leveeing, revetting and riprap p in g and excessive water wididrawals, 

 thereby disconnecting the rivers from their floodplains and groundwater systons. An estimated 70-90% of natural 

 riparian (streamside) vegetatioa, vital to maintaining the integrity of riverine ecosystems and biodiversity, has already 

 been lost due to human activities. Seventy perceot of the region's rivers have been impaired by flow alteration. 



Loss of private land lowland habitats has placed much of the burden of maintaining the healtti of both riverine 

 ecosystems and biodiversity oo the federal forest lands in the region. While federal forest habitats have also been 

 degraded, the best remaining habitats are found in the federal forests primarily in unloaded, steep watersheds dominated 

 by old growth forests. 



Even on the federal forests river reaches are degraded. Recent research has documented that fish habitat on National 

 Forests and other lands currently has fewer pools, higher fine sediments in spawning gravels and fragmented riparian 

 vegetatioa than is heahhy. For example, die mimber of large deep pools in many tributaries of the Columbia river have 

 decreased in the past SO years in resurveys completed between 1989 and 1992 by Forest Service researchers. Overall 

 there has beeo a 30 to 70 percent reductioa in the number of large, deep pools ( > 6fi. deep and > SO yd sur^ce ai«a) 

 on Natioaal Forests within anadromous fish in the past 50 years. A similar trend has been found in streams on private 

 lands in coastal and eastern Oregon, Wasfamgtoa, and Idaho where large deep pools have decreased by 60-80 perceot 

 Large pools are important for anadromous fish as holding areas for adults for spawning, refuge from drought and winter 

 icing, maintenance of fish communtfy biodiveraity and jovenik fiafa rearing areas. 



