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A.E. Thomas

Publications and source records attributed to A.E. Thomas.

6 recordsLinked to original sources
USGS1979

Survival of one- and two-year-old monosex grass carp in small ponds

Limited information has become available on the survival of monosex (female) grass carp (Ctenopharyngodon idella) reared in earthen ponds. Monosex fish produced in 1975 (Stanley 1976) were reared 27 months in earthen ponds at the Fish Farming Experimental Station, Stuttgart, Arkansas. Periodic transfers of these fish to different ponds afforded the opportunity to obtain survival information. Thomas and Carter (1977) reported first-year survival percentages of 22.9 to 60.2% (average 34%) for fry stocked in six 0.1-ha ponds in June and July 1975 in a test of different stocking densities and pond conditions. Overall, of 31,887 3-mm fry stocked. 10,035 survived to reach the large fingerling stage (80-250 mm) when they were removed from the ponds in April 1976.

Progressive Fish-Culturist↗
USGS1977

Survival of monosex grass carp in small ponds

Little information is available on the survival of grass carp (Ctenopharyngodon idella) in ponds &mdash especially on the survival of fry to large fingerling stage, during the time when the most mortality would be expected. Development of monosex (all female) grass carp at the Fish Farming Experimental Station by the technique of artificial gynogenesis (Stanley et al. 1975) enabled us to observe survival to the large fingersling stage under several stocking densities and pond conditions. These limited observations, made incidentally to other studies, may provide clues for the development of management techniques to reduce mortality. Monosex fry were used in these observations, but there is no reason to suppose that survival of bisexual fry would have been different.

Progressive Fish-Culturist↗
USGS1975

Effect of egg concentration in an incubation channel on survival of chinook salmon fry

Eyed eggs of chinook salmon (Oncorhynchus tshawytscha) were planted in the Abernathy (Washington) incubation channel at concentrations of 7,180, 10,764, and 14,349 eggs/m 2 of gravel. Numbers of eggs planted were 200,000, 240,000, and 200,800, and survivals to the downstream migrant stage were 78.5, 85.0, and 79.1%, respectively; the differences were not statistically significant. The concentration of 14,349 eggs/m 2 is near the capacity of the channel. This stocking rate is 10 times that commonly recommended for artificial spawning channels. Egg concentration was apparently limited only by the physical capacity of the gravel.

Transactions of the American Fisheries Society↗