|
<br />
<br />'4
<br />
<br />,strate produced 25,000 eggs and 7,500 fry (30%
<br />ching success); injected females that spawned nat-
<br />Ily on cobble substrate produced 55,000 eggs and
<br />/)0 fry (67% hatching success); injected females
<br />were hand stripped produced 78,540 eggs and
<br />iO fry (3% hatching success).
<br />urvival of squawfish progeny was excellent in the
<br />jified raceways. The fish were able to endure
<br />ure conditions including low dissolved oxygen
<br />mg/ L), high ammonia nitrogen (2.0 mg/ L), high
<br />.Jon dioxide (l5.0 mg/ L), high pH (9.0 units),
<br />rcrowding, and sudden fluctuations in water
<br />peratures (lOoC in 10 min). Although raceway
<br />ure might not be the ideal environment for rearing
<br />awfish progeny, until other methodologies are
<br />mpted and proven, it is certainy feasible and quite
<br />:juate.
<br />. spawning and rearing techniques are developed
<br />, the Colorado squawfish may again inhabit the
<br />;rs of the upper and lower Colorado River basin.
<br />:hery propagation and culture may be essential to
<br />estoration of this endangered fish species.
<br />
<br />:nowledgments
<br />
<br />'lank Lyle Miller, Peter Carboni, Joe Saenz, and
<br />:aff at Willow Beach National Fish Hatchery for
<br />.ance during this project, and James Johnson for
<br />wing the manuscript.
<br />
<br />erences
<br />
<br />l. c., and E. H. Bacon. 1954. Use of pituitary materials
<br />Ie propagaton of minnows. Prog. Fish-Cult. 16(3): 108- I I3.
<br />:ns, H. P., and K. E. Sneed. 1962. Bioassay and use of
<br />jitary materials to spawn warm-water fish. U.S. Fish
<br />dl. Servo Res. Rep. 61. 30 pp.
<br />
<br />Fish-Cult. 43 (4), October 1981
<br />
<br />,-
<br />/
<br />I
<br />
<br />Colorado River Fishes Recovery Team. 1978. Colorado
<br />squawfish recovery plan. U.S. Fish Wildl. Serv., Salt Lake
<br />City, Utah. 68 pp.
<br />Deacon, J. E., G. Kobetich, J. D. Williams, and S. Contereas.
<br />1979. Fish ofN orth America endangered, threatened or of
<br />special concern: 1979. Fisheries (Am. Fish. Soc.) 4(2):29-44,
<br />Jeppson, P. 1957. The control of squawfish by use of
<br />dynamite, spot treatment, and reduction of lake levels.
<br />Prog. Fish-Cult. I 9(4): I 68- I 7I.
<br />Joseph, T. W., J. A. Sinning, R. J. Behnke, and P. B.
<br />Holden. 1977. An evaluation of the status, life history, and
<br />habitat requirements of endangered and threatened fishes
<br />of the upper Colorado River system. Western Energy and
<br />Land Use Team, Fort Collins, Colo. 183 pp.
<br />Leitritz, E. 1960. Trout and salmon culture. Calif. Dep. Fish
<br />Game, Fish. Bull. 107. 169 pp.
<br />Minckley, W. L. 1973. Fishes of Arizona. Ariz. Game Fish
<br />Dep., Phoenix. 293 pp.
<br />Patten, B. G., and D. T. Rodman. 1969. Reproductive
<br />behavior of northern squawfish, Ptychocheilus oregon-
<br />ensis. Trans. Am. Fish. Soc. 98(1): 108- 110.
<br />Seethaler, K. 1978. Life history and ecology ofthe Colorado
<br />squawfish (Ptychocheilus lucius) in the upper Colorado
<br />River basin. M.S. thesis, Utah State University, Logan.
<br />172 pp.
<br />Toney, D. P. 1974. Observations on the propagation and
<br />rearing of two endangered fish species in a hatchery
<br />environment. Proc. Annu. ConE. West. Assoc. State
<br />Game Fish Comm. 54;252-259.
<br />U.S. Department of the Interior. 1980. Federal Register.
<br />U.S. Fish Wild!. Serv.. Washington, D. C. Part II. 45(99);
<br />33768-33781.
<br />Vanicek, C. D., and R. H. Kramer. 1969. Life history of the
<br />Colorado squawfish, Ptychocheilus lucius, and the Colo-
<br />rado chub, Gila robusta. in the Green River in Dinosaur
<br />National Monument. 1964-1966. Trans. Am. Fish. Soc.
<br />98(2): 193-208.
<br />
<br />Accepted 3 June 1981
<br />
<br />177
<br />
|