Survival and hatching success of stonefly eggs (paragnetina media) following ingestion by three stream fishes

Abstract

The effects of predation by three stream fishes (emerald shiner, creek chub, and mottled sculpin) on the survival and hatching success of eggs of the northern stonefly, Paragnetina media (Walker), were investigated with feeding and incubation experiments. Stonefly eggs displayed a 75% survival rate through the digestive system, but no statistically significant difference (p > 0.05) was observed in the recovery of intact eggs from the three fishes. Approximately 73% of the eggs that passed through the emerald shiners and mottled sculpins hatched within 60 days. Significantly fewer eggs (p = 0.002, 63%) hatched following passage through the creek chubs. Previous studies have shown that stonefly eggs can survive periods of freezing, desiccation, and harsh physical conditions. The present study shows that stonefly eggs can also survive passage through the digestive system of predatory stream fishes and this may represent a previously uninvestigated mechanism for localized dispersal. © 2000, Copyright Taylor & Francis Group, LLC.