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<br />"0 <br />o <br />(:::') <br /> <br />9 <br /> <br />, " <br /> <br />Based on the habitat analyses reported in Bliesner and lamarra (1995), there would appear <br />to be habitats above the known spawning area (the Mixer) and the low velocity habitats <br />downstream of the Mixer that share similar characteristics to these areas. These similarities <br />may possibly support spawning areas further upstream in the San Juan River, together with <br />habitats suitable for larval and young Colorado squawfish. The stocking proposal would allow <br />monitoring to determine if adult Colorado squawfish would utilize these upstream habitats for <br />spawning. If the fish do spawn at these upstream sites, information could also be gathered <br />on the habitat use of young Colorado squawfish above the diversion dams. <br /> <br />w <br />,.... <br /> <br />As previously stated, Colorado squawfish spawn July 1 to September 1 in cobble/gravel areas <br />typically found in riffle/run habitats. Following hatch, larval Colorado squawfish drift <br />downstream to low velocity habitats. Important habitats during summer low flow (August) <br />are the San Juan's backwaters and secondary channels, used by larvae and young Colorado <br />squawfish. During 1995 investigations under the San Juan Recovery Implementation <br />Program, low velocity habitats were more common in August than June and comprised a <br />greater percentage of total habitat upstream from RM 110 than downstream. low velocity <br />habitats peaked in abundance between RM 120 and RM 180 (Holden and Masslich 1995). <br /> <br />D. INTERRELATIONSHIPS WITH OTHER PROJECTS OR PROPOSALS <br /> <br />The proposal has been formulated to complement and support the existing stocking program <br />of juvenile Colorado squawfish in addition to the entire ongoing research effort for the <br />Implementation Program. The Program itself was established to foster such research and <br />coordinate the numerous activities ongoing and proposed for the San Juan River Basin with <br />potential to impact the endangered fish species. Other activities that may occur in the Basin <br />include, but are not limited to, the U.S. Army Corps of Engineers"permitting responsibilities <br />for dredge and fill activities in waters of the Untied States through section 404 of the Clean <br />Water Act, each respective State and Tribal resource agency's responsibilities for <br />management and protection of resident fish and wildlife resources, and other Federal, State, <br />and Tribal land management entities with responsibilities within the Basin. <br /> <br />II. ALTERNATIVES <br /> <br />A. NO ACTION <br /> <br />Under a No Action alternative, the 50 adult Colorado squaw fish currently available would not <br />be stocked. It is unknown whether other use could be made of these 50 fish in research <br />efforts. To date, the Service has inadequate facilities to take them back at Dexter NFHTC. <br />Other research commitments of the Implementation Program now underway would continue <br />and other, less timely and less efficient methods would be employed to gain the required <br />information on the species in the Basin. <br /> <br />B. STOCKING OF COLORADO SQUAWFISH IN THE SAN JUAN RIVER <br /> <br />The preferred alternative involves stocking 50 adult Colorado squawfish (now housed at the <br />Yankton, South Dakota, Research Facility of the U.S. Geological Survey) in the San Juan River <br />during the fall 1997. These fish were originally obtained from Dexter National Fish Hatchery <br /> <br />I <br />~ <br />