Six teams tested recommended procedures for estimating fish kill magnitude during a simulated fish kill in a small east Texas stream. Dead fish were added to the stream and counted 16 h later using accepted guidelines for sampling and counting dead fish. Thirty‐one percent of the 943 dead fish that were initially placed in the stream remained when teams counted fish. The highest estimate of dead fish included only 39% of the total number of dead fish added to the stream. Independent estimates were moderately variable (mean = 308, SD = 54) and accurate when compared with the number of carcasses remaining in the stream (N = 291) at the time of the investigation. Small individuals (<15 cm total length, TL) and less abundant species were underestimated to a greater degree than large individuals (>35 cm TL) and more abundant species. Counts involving fewer fish resulted in a greater underestimation of fish killed than did counts of larger numbers of fish. Complete enumeration gave the most accurate estimate of the number, species, and size distribution of carcasses remaining in the stream. However, all estimates grossly underestimated the total number of dead fish placed in the stream. Scavengers probably removed most of the dead fish during the 16 h before the investigation.

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Five of 18 blackside darter Percina maculata larvae and 3 of 18 leopard darter P. pantherina larvae collected in light traps from the Glover River, McCurtain County, Oklahoma, contained ingested items. The maximum diameter of prey ingested was between 0.27 and 0.37 mm and was 70–90% of their gape widths. None of the larvae that contained prey items possessed a visible yolk sac. Forty‐three of 48 laboratory‐reared larval dusky darters P. sciera offered zooplankton (≤0.30 mm in diameter; harvested from hatchery ponds) contained ingested items. The dominant prey was Ceriodaphnia spp. adults and neonates. The maximum number of Ceriodaphnia consumed by an individual larva was 20. Calanoid copepods were abundant in the zooplankton offered but were not found in any but the 18‐d‐old larvae. Rotifers in low densities also were offered, but none were observed in any of the alimentary canals. We conclude that small (≤0.30‐mm), pond‐ reared cladocerans such as Ceriodaphnia and Bosmina are suitable food for the first‐feeding Percina species examined during this study.

Past disturbance of eggs or larvae of dusky darters Percina sciera has resulted in almost 100% mortality of the larvae within 9 d of hatch. Photoperiod and water temperature were manipulated to induce dusky darters collected from the wild to spawn in the laboratory. Eggs spawned in gravel spawning trays were transferred while in the trays to specially designed egg incubators. Dusky darter larvae were collected after they emerged from the gravel and swam out of the incubator. Groups of larvae were offered ground TetraMin (≤0.3 mm), zooplankton (≤0.3 mm), or a combination of both foods in aquariums that had circulated or noncirculated water. The highest mean survival per treatment was for zooplankton and no circulation (71%); the lowest mean survival was for TetraMin with no circulation (3%). A dusky darter growth curve from egg to first spawn, approximately 1 year, was developed. Dusky darters reared in the laboratory from eggs were successfully spawned.