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Larval fish originating south of Cape Hatteras, North Carolina, are frequently found on the continental shelf north of Cape Hatteras, even as far north as the Scotian shelf. The Gulf Stream and associated warm-core rings are hypothesized as the physical mechanisms responsible for the northward transport of larvae. Specifically, larvae spawned along the southeast U.S. continental shelf are entrained into the Gulf Stream, transported to the northeast, regularly incorporated in warm-core ring streamers, transported across the slope region, and released along the shelf edge north of Cape Hatteras. This proposed transport route was evaluated using hydrographic data and drifter tracks that were collected as part of other studies. Continental shelf water that originated south of Cape Hatteras was found AcknowledgmentsPatricia Tester, Cecily Natunewicz, and David Chapman provided critical reviews of earlier drafts of this manuscript.

The diets of larval gulf menhaden Brevoortia patronus, spot Leiostomus x d n t h u~s , and Atlantic croaker Micropogonias undulatus, collected in the northern Gulf of Mexico in December 1979, February and December 1980, and February 1981, were significantly (P<0.001) different when compared with respect to length by step-wise discriminant analysis, and there was little overlap when the diets of size-specific larvae that CO-occurred in discrete collections were compared by percentsimilarity. Gulf menhaden larvae had a more diverse diet that included phytoplankters (diatoms and dinoflagellates) as well as zooplankters (tintinnids, pelecypods, pteropods, and all stages of copepods). The diets of larval spot and Atlantic croaker were largely restricted to zooplankton. Overall diet distinctiveness, the lack of diet overlap, and the lack of small-scale CO-occurrence indicate that the larvae of these three species do not compete for food.

SUMMARY: Fisheries oceanography can be defined as the study of the ecology of fishes in the ocean: so defined, it comprises study at all levels of ecological organization-organisms, populations, communities, and ecosystems. The early life history of fishes plays out at each of these levels of organization. A paradigm developed by Johan Hjort at the turn of the twentieth century, along with postulates by Hjort and many of his colleagues that followed, came to guide much of fisheries oceanography through the ensuing hundred years. Research themes that address these postulates can be roughly partitioned as the study of the physiological ecology of the eggs and larvae of fishes in the sea, and the study of the abundance and distribution of fish propagules. Using case studies of organisms and physical processes, considerable progress has been made in understanding the causes of variation in population recruitment, defined either by stage-based models and simulated by individual-based models. Some of this progress has been published in Scientia Marina, or its predecessor Investigación Pesquera. The causes of variation, however, are interactive and operative at differing, yet often overlapping, spatial and temporal scales. Difficulty in matching spatial scales that typically differ by an order of magnitude or more, will continue to trouble the resolution of causes of population recruitment. Moreover, study of the causes of variation in recruitment has not led to predictive power at an annual scale. Prediction at a decadal scale, using community (or more appropriately larval fish assemblages) and ecosystem level dynamics, is more hopeful. -La oceanografía pesquera puede ser definida como la ecología de los peces en el océano: definida de este modo, comprende el estudio a todos los niveles de organización ecológica: organismos, poblaciones, comunidades y ecosistemas. Los primeros estadios de desarrollo de los peces intervienen en cada uno de estos niveles de organización. El paradigma desarrollado por Johan Hjort a principio de siglo veinte, junto con postulados posteriores del propio Hjort y muchos de sus colegas, han servido de guía de la oceanografía pesquera de los siguientes cien años. Los temas de investigación a que conducen estos postulados pueden ser fundamentalmente divididos en el estudio de la ecología fisioló-gica de los huevos y larvas de peces en el mar y el estudio de la distribución y abundancia de los propágulos. Utilizando el estudio de casos particulares de organismos, se han conseguido considerables progresos en la comprensión de las causas de variación en el reclutamiento de las poblaciones, definido ya sea por los modelos basados en el estadio de desarrollo o en simulaciones basadas en el individuo. Algunos de estos avances han sido publicados en Scientia Marina, o en su predecesora Investigación Pesquera. No obstante, las causas de variación son interactivas y operativas a escalas espaciales y temporales distintas, o incluso solapadas. La dificultad para ajustar las escalas espaciales que típicame...

SUMMARY: The Indo-Pacific lionfish, Pterois miles and P. volitans, have recently invaded the U.S. east coast and the Caribbean and pose a significant threat to native reef fish communities. Few studies have documented reproduction in pteroines from the Indo-Pacific. This study provides a description of oogenesis and spawn formation in P. miles and P. volitans collected from offshore waters of North Carolina, U.S.A and the Bahamas. Using histological and laboratory observations, we found no differences in reproductive biology between P. miles and P. volitans. These lionfish spawn buoyant eggs that are encased in a hollow mass of mucus produced by specialized secretory cells of the ovarian wall complex. Oocytes develop on highly vascularized peduncles with all oocyte stages present in the ovary of spawning females and the most mature oocytes placed terminally, near the ovarian lumen. Given these ovarian characteristics, these lionfish are asynchronous, indeterminate batch spawners and are thus capable of sustained reproduction throughout the year when conditions are suitable. This mode of reproduction could have contributed to the recent and rapid establishment of these lionfish in the northwestern Atlantic and Caribbean.Keywords: lionfish, Pterois, oogenesis, ovarian peduncle, oocyte, invasions. RESUMEN: Ovogénesis y formación de la puesta de los peces invasores Pterois miles y Pterois volitans. -Los peces Indo-Pacíficos, Pterois miles y P. volitans, han invadido recientemente la costa este de los Estados Unidos y el Caribe y representan una significativa amenaza a las comunidades nativas de peces coralinos. Unos pocos estudios han documentado la reproducción en peces de la subfamilia Pteroinae del Indo-Pacífico. Este estudio presenta la descripción de la ovogénesis y la formación de puesta en P. miles y P. volitans recolectados desde aguas a mar abierto de Carolina del Norte, U.S.A, y las Bahamas. Mediante el uso de observaciones histológicas y de laboratorio, encontramos que no había diferencias en la biología reproductiva entre P. miles y P. volitans. Estas especies desovan huevos flotantes que están encerrados en una masa hueca de moco producida por células secretoras especializadas del complejo de la pared del ovario. Los ovocitos se desarrollan en pedúnculos altamente especializados, estando todos los estadios de los ovocitos presentes en el ovario de las hembras en puesta, y los ovocitos más maduros se localizan en la zona terminal, cerca del lumen del ovario. Dadas estas características del ovario, estas especies son asincrónicas, ponedores secuenciales indeterminados y son, por tanto, capaces de tener una reproducción sostenida a lo largo del año cuando las condiciones son adecuadas. Este modo de reproducción podría haber contribuido al rápido reciente establecimiento de estas especies en el noroeste del Atlántico y Caribe.

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Currents that effect the shoreward transport of the larvae of estuarine‐dependent fishes spawned in winter in Onslow Bay, North Carolina, USA, were driven by winds and pressure gradients, and influenced by the Gulf Stream. Aside from storms, winds over the continental shelf in Onslow Bay blew predominantly alongshore with velocities approaching 14 m s‐1 during February and March 1986, and January and February 1989. Water masses and currents observed at two current‐meter moorings, one at mid‐shelf and the other on the outer shelf, reflected the onshore (or offshore) advection of interior water in compensation for the offshore (or onshore) advection of wind‐driven surface water. Winds and currents reversed direction approximately every 4 to 6 days. The larvae of Atlantic menhaden, Brevoortia tyrannus, spot, Leiostomus xan‐thurus, and Atlantic croaker, Micropogonias undulatus, were most abundant in 17–19oC and 20–21oC water of the outer shelf and Gulf Stream fronts. There was little indication of diel vertical migration; larval Atlantic menhaden were most abundant in mid‐ and surface water, while spot and Atlantic croaker were most abundant in mid‐ and deep water. Given this distribution, the inferred advective transport of larvae was at times onshore, but at other times it was offshore. Within a spawning season, the prevalence of either reciprocation could determine the number of larvae that reach coastal inlets.