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<br />EXECUTIVE SUMMARY
<br />
<br />Historically, thc Colorado pikeminnow, Ptychocheilus lucius, occurred in the mainstem
<br />Colorado River and its tributaries from Wyoming to the Gulf of Califomia, The San Juan
<br />River in New Mexico and Utah contains a small population of Colorado pikeminnow.
<br />The Colorado pikeminnow was listed as a federally endangered species in 1967 (32
<br />Federal Register 400 I) and is protected under the provisions of the Endangered Species
<br />Act of 1973 (39 Federal Register] 175),
<br />
<br />In 1991, The U,S, Fish and Wildlife Service released a Biological Opinion which
<br />required seven years of research to be conducted on the San Juan River and it's
<br />tributaries. One element of the San Juan River Seven- Year Research Program was to
<br />determine habitat requirements of the endangered species found in the San Juan River.
<br />The habitat utilization data will be used to fulfill the long range plan objective 5,2,
<br />specifically 5,2,5 and 5,2,6 (San Juan River Recovery Implementation Program Biology
<br />Committee 1995), The objective of this study was to describe habitat use by adult
<br />Colorado pikeminnow during summer months in the San Juan River.
<br />
<br />This study determined Colorado pikeminnow habitat use during the summer in the San
<br />Juan River, New Mexico and Utah. Although the study area included the entire San Juan
<br />River, radio implanted Colorado pikeminnow were only contacted in Reaches 3,4 and 5
<br />for study years 1993 and 1994 and Reaches 5 and 6 for study year 1998, The most
<br />downstream contact occurred in 1994 near Bluff, Utah (RM 73,8), The farthest upstream
<br />contact was near Farmington, New Mexico (RM 178,8),
<br />
<br />Radio implanted fish were intensively tracked to determine both the location within a
<br />reach of river and the habitat use by those fish, Radio telemetry was conducted on seven
<br />wild adult Colorado pikeminnow that were opportunistically implanted in the spring of
<br />1993 (4 fish) and 1994 (3 fish) with radio transmitters by U,S, Fish and Wildlife Service
<br />(Grand Junction, CO) personnel. Seven hatchery-reared Colorado pikeminnow were
<br />intensively followed during the summer of 1998.
<br />
<br />Any locations where the fish remained for more than 30 minutes were recorded, and if
<br />possible, habitat parameters were measured, Data on habitat characteristics near the fish
<br />location were acquired by habitat mapping on aerial videography plates and digitizing the
<br />habitat maps. Habitat maps were created for each separate fish location during the
<br />observation day,
<br />
<br />Habitat usage data included a sketch of the habitat surrounding the fish locations and
<br />included fish positions marked on the map. Data collected at the fish location included
<br />date, time of day, weather conditions, time monitored, and any notes on movement
<br />during the observation period, When possible, other physical habitat data was collected
<br />at each fish location, These measurements included water depth, water velocity (mean
<br />column and bottom), substrate type, proximity to cover, description of cover at the
<br />location, general description of the site; measurements of the habitat type including
<br />
<br />Colorado Pikeminnow Habitat Use in the San Juan River, New Mexico and Uta.h
<br />Miller Eeologica' Consultants, Inc.
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<br />Page i
<br />Januar}' 31,2000
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