Although the reproductive behavior of yellow perch Perca flavescens has been well documented in small systems, relatively little is known about the spawning preferences of yellow perch in large systems, such as the Laurentian Great Lakes. During 2006 and 2007, we compared the presence and abundance adult yellow perch during the spring spawning season with environmental variables in the western ...

—Stock–recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Oh...

Identifying the target of sexual selection in externally fertilizing taxa has been problematic because species in these taxa often lack sexual dimorphism. However, these species often show sex differences in spawning behavior; males spawn before females. I investigated the consequences of spawning order and time intervals between male and female spawning in two field experiments. The first invo...

Approximately 20% of North American minnows are considered imperiled. The factors responsible for imperilment in this group are complex, but the relationship of spawning mode to conservation of North American minnows has not been explored. 1 provide a summary of the spawning modes of imperiled North American minnows, discuss patterns between these modes and conservation status, and predict the ...

The external appearance of brood fish has long been used to assess the stage of sexual development. In some species, males change in appearance during the spawning season (e.g., vivid breeding colors in cichlids, hooked jaw in salmon, and roughened texture of the pectoral fins or head of cyprinids). These physical changes make it relatively easy to identify sexually mature males. However, secon...

Background: The objective of the present study was to examine the effect of Ovaprim dosage on the latency period, relative number of ovulated eggs, fertilization, hatching, and survival rates of the siban fish, Cyclocheilichthys apogon. Methods: Three dosages of Ovaprim were tested in this study, namely 0.3 ml kg-1 of broodfish body weight, 0.5 ml kg-1 body weight, and 0.7 ml kg-1 body weight, ...

The objective of the present study was to examine the effect of Background Ovaprim dosage on the latency period, relative number of ovulated eggs, fertilization, hatching, and survival rates of the siban fish, Cyclocheilichthys . apogon : Three dosages of Ovaprim were tested in this study, namely 0.3 ml Methods kg-1 of broodfish body weight, 0.5 ml kg-1 body weight, and 0.7 ml kg-1 body weight,...

-During their first year in captivity, summer flounder Parulicthys denratus were induced to spawn with gonadotropin releasing hormone analogue (GnRHa) implants, injected carp pituitary extract (CPE) or human chorionic gonadotropin (hCG) injections. The percentage of fertile eggs was greatest (-69%) in CPEtreated females. CPE, but not GnRHa or hCG, was capable of stimulating oocyte growth (incre...

Reproduction in fishes is regulated by external environmental factors that trigger internal mechanisms into action. The final event of the reproductive cycle, the release of eggs and sperm resulting in spawning, can be controlled by either placing the fish in an appropriate environment or by changing the fish’s internal regulating factors with injected hormones or other substances. The internal...

This study investigates the fate of sediment suspended due to dredging in Newark Bay, New Jersey to characterize exposure of winter flounder spawning habitat. Winter flounder is a recreationally and commercially significant species which has experienced a steady population decline over the last twenty years. Winter flounder eggs are demersal and adhesive. Possible factors affecting spawning hab...