A new device for collecting drifting semibuoyant fish eggs

Several fish species in lotic systems are pelagic broadcast spawners that p roduce nonadhesive, semibuoyant eggs that drift downstream. This reproducti ve strategy and egg type appear to be common in Plains stream cyprinids in the west-central United States. Although it is relatively easy to capture s emibuoyant eggs, the inability to provide species-specific identification o f this life stage has hindered studies on the reproductive ecology and life history of these fishes. While drift nets have been used to collect semibu oyant eggs, the process of separating the reproductive products from other organic drift was time consuming and usually fatal for eggs. We developed a held sampling device, the Moore egg collector, that allowed for the effici ent, quantitative, and nondestructive collection of large numbers of semibu oyant fish eggs and that could aid in the study of a variety of organisms t hat employ drift as a dispersal strategy during a portion of their life his tory.