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<br />551 <br /> <br />November 18-24,1996 <br />This trip began on November 18th, two weeks following the stocking. Two crews were used to <br />complete this trip. One crew sampled the river from Shiprock to Sand Island. The first five miles <br />below Shiprock as well as the other UDWR nursery habitat reaches (Mixer and Montezuma <br />Creek) were intensively sampled (Le., low-velocity habitats, backwaters, eddies, and shorelines). <br />Less intensive sampling (at least two habitats per 5 mile reach) was completed on the remainder <br />ofthe river. A total of 110 Colorado squawfish were caught with the following distribution: 67 <br />in first five miles, 10 between RM 143-131, 9 between RM 131-126, 22 between RM 126-89, 2 <br />between RM 89-84, and none between RM 84-78 (Table 2). These fish were mainly in flow <br />through type backwaters and secondary channel pools. Only one Colorado squawfish was caught <br />in a backwater, however, few backwaters existed and the ones that did, were shallow in this <br />reach. The other crew sampled the river from Mexican Hat to Lake Powell with the methods <br />described above. A total of399 stocked Colorado squawfish were collected in the lower reach <br />with the following distribution: 141 between RM 52-42, 72 from RM 42-25, 84 from RM 25-20, <br />and 102 from RM 13-7 (Table 2). All but one of these fish were collected with shoreline and low <br />velocity habitat seine hauls. When "classic" nursery habitats (backwaters) were available, <br />Colorado squawfish used them. The remainder of the fish were collected on shallow shoreline <br />benches. The fish averaged 55.2 mm. Fluorescent pigment was detected on approximately Y, of <br />the fish encountered. Several fish encountered in the lower reach were released at Shiprock. One <br />Colorado squawfish was found 140 river miles below its release site. - <br /> <br />December 9-15, 1996 <br />Reach RM's <br />Crew 1 148--76 <br />Crew 2 53-0 <br /> <br />Dates <br />12/08/96--12/15/96 <br />12/08/96-12/14/96 <br /> <br />Effort: The first five miles below the stocking sites (Shiprock bridge RM 148 and Mexican Hat <br />RM 53) were intensively sampled with seine and electrofishing gear. A total of 13 different <br />habitats were sampled by the upper crew in this reach resulting in 27 samples. Crew 2 sampled 21 <br />different habitats resulting in 25 samples, in the first five miles. All habitats encountered in the <br />four nursery habitat sections were also intensively sampled. Throughout the remainder of the <br />river, one secondary channel and one flow-through backwater per 5 river miles were sampled by <br />Crew 1. Crew 2 sampled two low-velocity sites (this consisted primarily of seining backwaters <br />and low-velocity flow-throughs) per 5 river miles throughout the remainder of the river. A total <br />of 154 samples were collected by Crew 1 and 160 by Crew 2. Ten Colorado squawfish from each <br />of the intensively sampled reaches were preserved in 95% ethanol for stomach analysis, lipid <br />content evaluation, and to determine the presence of the tetracycline mark_ High turbidity <br />reduced electro fishing effectiveness. <br /> <br />Results - Crew 1: One hundred and ten Colorado squawfish were collected by Crew 1 (Table 2). <br />Colorado squawfish were collected in 43 separate samples. In 24 samples, more than one <br />Colorado squawfish was collected. Colorado squawfish were collected in flow-through <br />backwater type habitats, shorelines, and secondary channels. The majority of Colorado squawfish <br />were captured in small secondary channel pools with depths greater than 1_0 ft (0.3m). At most <br />sites, the first two or three pools were sampled; the majority contained Colorado squawfish. <br /> <br />11 <br />