Author
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Ludwig, Gerald |
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Submitted to: Aquaculture Magazine
Publication Type: Trade Journal Publication Acceptance Date: 1/15/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Rosy red fathead minnows are the fourth most valuable baitfish/feeder fish in Arkansas, the site of 70 percent of all commercial baitfish culture. Producers often report losing nearly all the rosy reds stocked into their ponds after warm and wet winters. The rains soften roads that surround the ponds and prevent farmers from feeding their fish. High temperatures raise fish metabolism enough so that they need to be fed. Underfed fish move to the surface where they become easy targets for birds. This article reports on research that Gerald Ludwig has conducted at SNARC comparing compared the survival of rosy red and normal-colored fathead minnows in deep and shallow ponds in summer and winter. He also compared the two color varieties from ponds that received high and low daily feed rations. Unlike the conditions on many commercial ponds, Ludwig's ponds had few avian predators present. Ludwig found that ponds with average depths greater than 3.6 feet provided protection against high summer and low winter temperatures and the minnows receiving higher feed rations had much greater pond production and survived in better condition than minnows receiving the low rations, particularly during winter. Very few differences were found between the color varieties. Technical Abstract: Great differences in mortality between rosy red and normal-colored fathead ws have been reported by fish farmers. Survival and condition were increased when the fish were cultured in ponds averaging more than 2 ft deep and when the fish were offered rations of 2 percent of body weight daily during winter and 3% during summer. The deeper ponds provided a thermal refuge during the summer and winter. The feed rations resulted in fish doubling their weight and maintaining good body condition during winter, and having a five-fold weight increase during summer, thus assisting the minnows in avoiding avian predators |
