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All native big river fishes, including pallid sturgeon, evolved <br />with the cycle of precipitation and runoff inherently part of <br />the climate and geography of the basin or subbasin. <br />Reproduction of predator and prey was timed with this pattern <br />of water discharge. It is essential that the temporal and <br />spatial patterns be restored, in part, if recovery of native <br />fish species such as the pallid sturgeon will be realized. <br />Additional research in development of simulation models will <br />refine alternative operation scenarios that will best meet the <br />needs of pallid sturgeon and other beneficial uses. See <br />Task 2.2.2. <br />1.1.3. Restore the natural temperature regime of the Missouri River. <br />Main stem dams on the Missouri River operate with hypolimnetic <br />releases that have significantly decreased water temperatures <br />below dams during ice -free periods. These colder water <br />temperatures have changed species composition and very likely <br />have adversely affected spawning activities of pallid sturgeon. <br />Opportunities to restore warmer water temperatures within high - <br />priority recovery areas of the Missouri River should be <br />investigated and implemented. Further research on design and <br />practicality of multi -level releases from reservoirs is needed. <br />See Task 2.2.3. <br />1.1.4. Restore large woody debris to the main stem Missouri and <br />Mississippi Rivers and their larger tributaries. <br />Snags were physically removed from reaches of these rivers as a <br />engineering tool to improve navigation. Also transport of <br />trees from the floodplain has been reduced by control of <br />overbank flows. This large woody debris originally provided by <br />natural flood conditions provided essential instream habitat <br />for native big river fishes and for the insect life that these <br />fishes feed upon. Snags were instrumental in creating <br />depositional areas with diverse conditions of depth and <br />velocity within the main channels, slowing the transport of <br />organic matter, reducing channel velocity, and maintaining <br />diversity in bed substrates. Large woody debris should be <br />reintroduced into the river system on a regular basis. A <br />guideline for placement of snags and other large woody debris <br />needs to be developed. Also ongoing snag removal programs need <br />to be reviewed and reduced or terminated. Large woody debris <br />can come from trees cut from riparian woodlots and /or using <br />storm damaged trees from communities near rivers. <br />1.1.5. Restore the dynamic equilibrium of sediment transport within <br />the Missouri River. <br />Main stem Missouri River dams have trapped sediments in <br />reservoirs and bank stabilization has reduced erosion in <br />riverine reaches. Additional sediment input, initially within <br />25 <br />