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fatheads in each pond. To increase productivity, ponds were fertilized on <br />two occasions with Triple Super Phosphorus (45% available phosphoric acid) <br />at a rate of 2.3 kg/acre ft. <br />Blectrofishing and trammel-netting were used to capture seven adult Colorado <br />squawfish for use as broodstock. These fish were collected during May 12-23 <br />from the Colorado River between Grand Junction and Clifton, Colorado (RMI <br />165.5-175.1) and transferred to a holding pond at the Tiara Rado golf course <br />in Grand Junction. This pond was chosen because it was secure from <br />unauthorized access and it could be easily seined. We periodically seined <br />the squawfish from the pond, weighed them and made observations on the <br />external signs of their seasonal reproductive development. When the males <br />were producing milt that could be easily expressed when external pressure <br />was applied, we anticipated that the female fish too would be in near-ripe <br />condition. We then injected the females with an extract of carp pituitary <br />to induce ovulation. <br />As later discussed in Results, captive female brood fish failed to fully <br />ripen in the pond; thus we were unable to obtain fry from wild parents <br />during this initial attempt. We therefore stocked the rearing ponds with <br />hatchery-produced young. These were hatched at Dexter National Fish <br />Hatchery (NFH) in June and reared at Willow Beach NFH. On 28 August, the <br />squawfish were transported from Willow Beach to the ponds in a hauling tank <br />equipped with bottled oxygen and a water circulation system. Tank <br />temperature was 16 C upon arrival, so pond water (24 C) was added until the <br />tank temperature reached 21 C. Approximately 7,000 squawfish (28-61 mm <br />long) were stocked into each pond. Subsamples of stocked Colorado squawfish <br />(n = 100) were held in live-cages in each pond for 62 hr after stocking to <br />19