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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.

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.

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