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DRAFT DRAFT DRAFT <br />Geomorphology: Geomorphology is described as the set of interactions <br />between flow, sediment transport, local geology, and in some cases, vegetation, <br />that result in the physical template for aquatic and riparian life forms. For the <br />purposes of the Dolores River Dialogue, geomorphology is focused on how past <br />and future predicted flows affect this physical template; thus it is considered the <br />driving force behind ecological community potential for a given reach. The main <br />conclusion of the Geomorphology authors in the Core Science Report is that <br />flows are the dominant factor affecting physical and ecological processes, and <br />flow management for ecological objectives presents a key opportunity to improve <br />ecological conditions below McPhee Dam. <br />Riparian Ecology: Riparian ecology is the study of near-stream vegetation that <br />in some way, is dependent upon or determined by river flows or river processes <br />to satisfy the habitat requirements for riparian vegetation. Most changes in <br />community structure do not result from a single event or single stressor but from <br />multiple interacting causes within a particular riparian corridor. Riparian <br />vegetation plays a key role in the human-valued services provided by rivers and <br />also provides the fundamental structure for diversity of flora and fauna found <br />along the river. A variety of factors influence the structure and composition of <br />riparian vegetation growing along a particular reach of river, such as flows, <br />salinity and soil type. The DRD should remain informed about how flow <br />management affects the succession of riparian communities on the Dolores <br />below McPhee Reservoir. When opportunities for restoration arise, especially <br />with respect to tamarisk abatement or recruitment of native vegetation, the DRD <br />needs to assess how flow management can support the restoration objectives. <br />Cold Water Fishery: Cold water fisheries support fish that prefer clear, cold <br />waters. Cold water species are not tolerant of extreme temperature changes and <br />cannot survive for long periods with temperatures above 68 degrees F. In the <br />Dolores River below McPhee these are primarily rainbow trout and brown trout in <br />the upper reaches described above. Limiting factors for cold water fisheries <br />below the dam remain high summer water temperatures during baseflow periods, <br />and a lack of high quality trout habitat, especially in Reach 1 (McPhee Dam to <br />the Bradfield Bridge). Prolonged non-spill periods affecting geomorphic <br />processes such as flushing of fines from pools and riffles and sorting of spawn- <br />sized gravels also affect trout reproduction and survival through the upper <br />reaches. <br />Warm Water Fishery: At some point below McPhee Dam (generally in <br />Reaches 2 and 3), warm water temperatures favor fish adapted to warm water <br />conditions. The focus of the DRD for warm water fisheries is on the population <br />viability of endemic native fish, specifically diminishing populations of roundtail <br />chub, flannelmouth sucker, and bluehead sucker. State fisheries managers have <br />prioritized additional monitoring of native fish populations in the Dolores to <br />discern population trends at different representative sites between McPhee Dam <br />and Bedrock in order to define more clearly what factors are affecting native fish <br />populations in the Dolores. Some possible factors include poor habitat quality <br />9/5/06 1 1 <br />