During the 1960s and 1990s, the California Department of Fish and Game tagged 8,634 barred sand bass in southern California, and 972 fish (11%) were recaptured. Tag returns suggest barred sand bass are transient aggregate spawners that form spawning aggregations consisting of both resident and migrant individuals. Spawning residency at a historic spawning location was estimated by the frequency of returns over time; most same-year returns (82%, n = 141) were recaptured within a 7 to 35-day period. The maximum recapture distance was 92 km. The average (+ SD) non-spawning season recapture distance from peak spawning season tagging locations was 13 + 8 km, and movement was generally northward. A positive relationship existed between fish size (TL) and migration distance to nonspawning season recapture locations. Fish tagged at a presumed non-spawning season residence were primarily recaptured south of the tagging location during peak and late spawning season; the average migration distance was 17 + 15 km. Recaptures in subsequent years showed a high degree of spawning (80%, n = 135) and non-spawning (73%, n = 11) site fidelity. This is the first documentation of the spawning-related movements of barred sand bass and will be important for informing management decisions regarding this popular sport fish.Interpretations from Two Decades of Historical Tag and Recapture Data."
The yellowfin croaker, Umbrina roncador Jordan & Gilbert, 1882, is a common nearshore and surf-zone species in the southern California bight. Age was determined for individuals (n ¼ 1,209) using annual increments in otoliths, and size at age was modeled using the von Bertalanffy growth curve (L . Age and growth modeling based upon otolith length (OL) and width (OW ) measurements were assessed and were consistent with body measurements. Males and females were found in all size classes and in an overall 51 : 49 ratio that was not significantly different from a 50% sex ratio, suggesting that these fish are gonochores. Fish were reproductive during summer months, with gonadosomatic indices (females, 5.65%; males, 5.51%) consistent with group-spawning fishes. Data from two separate monitoring programs indicated that yellowfin croaker catch-per-unit-effort (CPUE) fluctuated appreciably from 1992 to 2006 on both spatial and temporal scales. CPUE also declined significantly in the latter years of these programs. Based on samples collected between 2003 and 2004, an estimate of overall annual total mortality was A ¼ 0:4492, and instantaneous coefficient of total mortality was estimated at Z ¼ 0:5964. Recruitment year classes were back calculated using annual survivorship. Year class strength was variable and declined significantly by the end of this study. Considering the high temporal and spatial variation in estimates of abundance and recruitment, coupled with the likelihood that these fish employ a probable group-spawning reproductive behavior, we recommend a cautious approach for the future management of this species.
Spotfin croakers Roncador stearnsii, a prized recreational catch, were collected throughout the Southern California Bight, primarily as bycatch from a long‐term, scientific gill‐net collection effort. The maximum otolith‐based age in the present study was 24 years—14 years greater than in a previous scale‐based aging study. Multiple models were used to estimate mean length at age, including models that utilize larvae as well as juveniles and adults, and the model selection results suggest sexual dimorphism in growth patterns. The juvenile and adult catch per unit effort reflected a clear pattern of habitat selectivity, with fish strongly preferring soft‐bottom habitats. Catches in rocky‐reef areas were limited but tended to increase with water temperature. The data also suggest that spotfin croakers segregate themselves sexually during the spawning season, when recreational fishing from jetties will target males and fish caught in bays and estuaries are more likely to be spawning females. These results provide further evidence for the importance of protection and restoration efforts for estuaries and bays along this well‐developed coastline. The growth of larvae captured in plankton tows in July and September 2004 was substantially faster than that of larvae sampled in May, which coincided with warmer sea surface temperatures, highlighting a potentially important relationship relating temperature (and therefore geography) and settlement success.
Received April 6, 2011; accepted November 27, 2011
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.