Estudio del desarrollo gonadal del Jurel dentón (Pseudocaranx dentex) asociado a jaulas de engorde de peces en aguas de Canarias

[ES] El jurel dentón Pseudocaranx dentex (Bloch & Schneider, 1801) es una especie habitualmente asociada al entorno de instalaciones comerciales de engorde de doradas Sparus aurata L., 1758 y lubinas Dicentrarchus labrax (L., 1758) en jaulas flotantes en las islas Canarias. Con el objetivo de conocer el potencial de esta especie para la acuicultura se ha llevado a cabo un estudio de su ciclo reproductivo anual. Durante un año se han recogido muestras de gónadas, evaluado variables morfométricas a partir de especímenes salvajes y registrado los valores de temperatura y fotoperiodo en el momento de los muestreos. Los análisis macroscópicos y microscópicos realizados de las gónadas, junto con la determinación mensual del índice gonadosomático (IGS) y del factor de condición (FC), han servido para establecer el ciclo anual de maduración de esta especie. El estadio de vitelogénesis avanzada fue observado entre mayo y noviembre, sugiriendo un prolongado periodo de desove para esta especie en aguas de las islas Canarias.

Evolución de la maduración gonadal de ejemplares de Seriola dumerilli mantenidos en cautividad

[EN]The present work describes the evolution of Seriolla dumerilli stock in the Instituto Canario de Ciencias Marinas from year 2006 to 2009. Nine sub adults of kingfish were captured by local fisherman in the south coast of Gran Canaria in may 2006, fish were transported in a truck and transferred to on land facilities. Adaptation to tanks and inert food was successfully carried out one month after the capture. After 3 year kept in captivity 100% survival was obtained. Initial fish weight (1,66kg), was increased over to 8,0 kg nowadays. Every year fish were sampled to determine individual growth in weight and size. In addition, the evolution of its sexual maturity state was established by ovarian biopsy. Oocites over 500 microns were observed in year 2008 in one of the females with an average weight of 3,8kg. In year 2009, mature fish were observed, but natural spawn was unsuccessful, however the use of hormonal injection (LHRH) results in two successful spawn with around 0,5 millions eggs (99% unfertilized eggs).

Sexualidad y reproducción del boquerón o longorón "Engraulis encrasicolus" (Osteichthyes: Clupeiformes: Engraulidae) en aguas de Gran Canaria

Máster en Gestión Sostenible de Recursos Pesqueros

Reproductive biology of the sea cucumber Holothuria sanctori (Echinodermata: Holothuroidea)

[EN] The reproductive biology of the sea cucumber Holothuria sanctori was studied over 24 months (February 2009 to January 2011) at Gran Canaria through the gonad index and a combination of macro- and microscopic analysis of the gonads. Holothuria sanctori showed a 1:1 sex ratio and a seasonal reproductive cycle with a summer spawning: the mean gonad index showed a maximum (3.99±0.02) in summer (June-July) and a minimum (0.05±0.04) between late autumn (November) and early spring (March). Females had significantly wider gonad tubules than males. First maturity occurred at a size of 201 to 210 mm, a gutted body weight of 101 to 110 g and a total weight of 176 to 200 g. Holothuria sanctori shows a typical temperate species reproduction pattern. These results could be useful for managing current extractions of H. sanctori in the Mediterranean and in case a specific fishery is started in the eastern Atlantic region.