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~ temperature and to allow for evaporation: Gravel was placed in the first thirty feet of the holding raceway during January and February 1974. Water depth over the gravel ranges from zero to twenty-four inch~s. Approximately half of the gravel surface consists of one inch or less aggregate. The other half consists of stones three to twelve inches in diameter. The gravel bed extends above the surface of the water at the head end of the raceway. Water introduced at the head end flows through the gravel. Feed and G rO\oJth Attempts to entice the broodstock to accept any feed other than live trout have been futile. They will take trout pellets, and even rocks, into their mouths, but \Jill not swallow them. The squawfish appear to be a very rapid s~limmer and fully capable of catching healthy trout, "but seldom do so. They prefer crippled trout and we oblige them by pinching the heads of the trout. We have no set frequency for feeding. Generally, the fish are fed all they Hill take three to four times a week. Size of feed has varied from one to four inches. The seven fish have taken as many as 160 three-{pch trout at one feedir:g. Approximately two pounds.. . Growth over the period from August 21, 1973 to May 30, 1974 has been slow, to say the least. At the beginning of this period, seven fish weighed 22.7 pounds. On January 10, 1974, they weighed 22.8 pounds. On May 30th, the six remaining 'fish ~Jeighed 20.6 pounds. The fish that died would have weighed a maximum of three point five pounds. This totals to a maximum weight of 24.1 pounds, for a gain of 1.4 pounds over a nine-month period. Considering approximately ninety pounds of trout were fed over this period, the conversion of food to fish flesh was not too good. - . _ The length weight relationship of our fish is very close to the length weight data furnished by (Vanicek and Kramer, 1969). Their calculated length and weight for ten and eieven year old fish was 570 and 600 millimeters and 1575 and 1850 grams. In comparison, two of .OL.!r fish \'Jere 531 and 594 ~illimeters and 1388 and 1900 grams, respectively. Unfortunately, we had not taken scale samples from these fish. We have subsequently done so, but have not had them read at this writing. Disease Examination for disease organisms was initially performed by Hatchery Biologist, Bruce Rosenlund on August 1, 1973. The only organisms found were Myxobolus, Lernaea and Ichthyophthirius. Saprolegnia on damaged areas of ~he epitheleum, gi 11 netting, was painted with a 1/1000 sol ution of potassium permanganate. After the initial loss of the injured fish, the balance appeared to be in excellent condition until the last of February 1974. At this time, a he<3vy inf('stati-'n of Ich was noted.' ~ ?C:'-1