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The aim of this study was to analyse the growth and reproductive biology of Gymnocephalus in Lake Piediluco, Italy. From June 1999 to March 2002, and between July 2004 and May 2005, 1,330 specimens belonging to seven age-classes were captured. Sex was determined in 385 individuals: 327 females and 58 males. Our results showed that in Lake Piediluco ruffe grow as fast as in their original environments. Seasonal growth and back-calculation showed the possible existence of differential mortality prejudicial to small specimens. Moreover, growth analysis revealed market sexual dimorphism in growth in the Lake Piediluco population. Sexual maturation occurred in both sexes at the end of the first year of life. Reproduction occurred mostly in May and June. The mean diameter of eggs was 1.12 mm. The mean number of eggs produced by each female was 11,961 and increased with the size of the specimens.

The reproductive biology of female Pasiphaea japonica, including the minimum size of females carrying embryos, spawning and hatching seasons, and brood size, was examined in Toyama Bay, central Japan, during 2004 through 2007. Sampling was conducted onboard a commercial seiner and a fisheries research vessel. The minimum size of ovigerous females was 47.7 mm body length. The percent occurrence of ovigerous females increased with body size, reaching 50% at 57.9 mm body length. Ovigerous females occurred all year round with a seasonal change in percent occurrence, ranging between 41.5 and 94.3% of the total observed females. Consequently, reproduction in females seems to occur throughout the year in Toyama Bay, with seasonal differences in reproductive intensity. Spawning intensity was high during April-July and October-January based on the occurrence of the early developmental stage of embryos, while hatching intensity was high in October-May based on the occurrence of embryos just before hatching. Brood sizes were similar at the same size of body length regardless of embryo stage, except just after spawning.

En este trabajo analizo el Proyecto de Desarrollo Pesquero que financió la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO) en Argentina entre 1965 y1974. El Proyecto de Desarrollo Pesquero buscó contribuir a solucionar el problema del hambre en el mundo mediante el incremento y la diversificación de la actividad pesquera en el Atlántico Sur. Más allá del alarmismo movilizado por la FAO, indago cómo las cooperaciones científicas internacionales contribuyen a establecer problemas científicos y sociales en las agendas de los países periféricos, antes que simplemente tender a solucionarlos. Para ello, retomo discusiones recientes sobre los efectos de las cooperaciones científicas internacionales en el marco de relaciones asimétricas entre países centrales y periféricos. Trabajo con documentos institucionales de la FAO y del Instituto de Biología Marina de Mar del Plata para reconstruir sus cooperaciones, objetivos cognitivos y económicos y la forma en que problematizaron la pesca y, en particular, la biología pesquera. Concluyo que la FAO contribuyó, en alianza con investigadores locales, a instalar en las agendas públicas que el Mar Argentino estaba siendo subexplotado y que esto justificaba su apertura a los grandes capitales extranjeros. Este diagnóstico científico tuvo profundos impactos en el desarrollo futuro de la pesca y algunos de los presentes problemas medioambientales del Mar Argentino.

Para obtener antecedentes reproductivos y poblacionales de Thais chocolata que contribuyan a validar su actual normativa pesquera, se realizó un estudio en el área protegida de la reserva marina La Rinconada, Antofagasta, Chile, entre diciembre 2008 y enero 2010. Los resultados obtenidos indicaron a nivel reproductivo, que el desarrollo gonadal de la población es asincrónico, encontrándose ejemplares en diferentes etapas de maduración durante el año. Los individuos maduros se estratificaron entre 5 y 13 m de profundidad, y gran parte del año formaron agregaciones a 5 m de profundidad. Se determinaron períodos de mayor madurez en julio-agosto, y en noviembre-enero, manifestándose las agregaciones más importantes al final de ellos. Una relación se observó entre meses de mayor madurez y registro de agregaciones, con aquellos de mayor variación intradiaria de temperatura. A nivel poblacional los resultados permitieron estimar una población de 2,3*10(6) ejemplares, donde el 39% se encontró sobre la talla mínima legal (TML = 55 mm). Los parámetros de crecimiento mostraron crecimiento relativamente lento, que podría estar influenciado por la alta variabilidad que presenta la temperatura de fondo en este sector. Mientras que su talla crítica, y la talla de primera madurez sexual poblacional, resultaron ser mayores a la TML. Se determinó la necesidad de revisar la normativa pesquera actual de esta especie, y se demostró la efectividad de las reservas marinas propiciadas por el Estado en la conservación de los recursos marinos.Reproductive and population parameters of Thais chocolata that would contribute to the validation of the current extraction standards were obtained by performing a study in the protected area of La Rinconada Marine Reserve, Antofagasta, Chile, from December 2008 to January 2010. In terms of reproduction, the results revealed asynchronic gonad development in the population, with specimens in different stages of maturity throughout the year. Mature individuals were distributed between 5 and 13 m depth, forming aggregations at 5 m depth during much of the year. Periods of greater maturity were observed from July to August and November to January, with the most important aggregations at the end of both periods. A relationship was observed between the months with the greatest maturity and aggregations and the months with the highest daily temperature fluctuations. At the population level, the results allowed us to estimate 2.3*10(6) individuals, with 39% of this population over the minimum legal size (55 mm). The relatively slow growth estimated for this population was probably influenced by the high variability of the bottom temperature in this area. The critical size and size at first maturity of the population were higher than the minimal legal size, making it is necessary to review the current fishing regulation for this species. The effectiveness of the State marine reserves in the conservation of this marine resource was demonstrated.

This circular describes the deliberations of the Workshop on Fishing-vessel Execution of Acoustic Surveys for Deep-sea Species: Main Issues and Way Forward that was held at the FAO headquarters from 9 to 11 December 2009. The topics considered by this workshop included the conditions required at sea for successful fishing-vessel deepwater acoustics surveys, the equipment to be used and its maintenance, processing of data, the problems arising from uncertainty in the backscattering cross section-biomass relation, survey methods, the estimation of biomass abundance and the associated uncertainties, the nature of supplementary biological data that are required for interpretation of acoustic information, use of the results, funding of survey programmes and recommendations for considerations in implementation of fishing-vessel executed deepwater acoustic surveys. The circular documents the meeting summary and the main recommendations with respect to general considerations, institutional and organization issues, applications at sea and operational challenges, vessels and equipment, survey methods, acoustic data processing and backscattering cross-section values, estimation of abundances, uncertainty of results, importance of collection of biological data, incorporating industry survey results into assessments and management process, funding of cost of acoustic surveys and discussions.

This synopsis compiles and reviews the currently available information on the biology, fisheries and cultivation of the ormer, Haliotis tuberculata. Topics include taxonomy, morphology, distribution, reproduction, pre-adult and adult stages, food and feeding, growth, movement, population characteristics, and various aspects of exploitation and culture. Data and information were obtained from both the more formal scientific publications as well as less formal journals, newsletters, regular reports and theses, as acknowledged in the text.