| Abstrakt: |
Interactions between fishing and the reproductive biology of an exploited stock are broader than the parameters historically considered (e.g., spawning seasonality, spawning biomass, and size or age at maturity). However, few studies address these broader interactions. Here we characterize a spawning aggregation of common snook , evaluate the feasibility of acoustic telemetry for monitoring the movement of released fish out of the spawning aggregation, and determine whether the stress of capture and release affects reproductive output. A spawning aggregation of common snook was studied in Lake Worth Inlet, Florida, during summer 1998 and 1999. The aggregation was made up of large, mature fish that were actively spawning, as indicated by females with hydrated oocytes or postovulatory follicles and males with flowing milt. Individual courtship behaviors by a few fish were observed by divers, but no spawning events were observed. Acoustic telemetry indicated that the stress of capture and release did not cause fish to immediately leave the aggregation. However, some individual movement into and out of the aggregation site was observed during the spawning season. Fish implanted with either live or dummy ultrasonic tags continued to spawn. Histological evidence suggested that the stress of being caught on hook and line and then released did not cause females to interrupt or terminate spawning. Released females were consistently recaptured from the aggregation, and levels of ovarian atresia and spawning activity were similar for both recaptured and control fish. [ABSTRACT FROM AUTHOR] |
Plný text