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.

Reproductive biology of the island grouper (Mycteroperca fusca) in the Canary Islands, northwest coast of Africa

[EN]This is the first time that the reproductive characteristics of Mycteroperca fusca have been analyzed over the whole area of its distribution, using the parameter of the histological analysis of the gonads. This species is a protogynous hermaphrodite with a marked predominance of females (1:4.9). The males and females displayed marked differences in the distribution of the sizes. The females were distributed over all the size ranges analyzed (229-725 mm total length), whereas the males were observed within the larger sizes, as of 428 mm. One transitional specimen (610 mm total length) was observed. The size at which the females first reached sexual maturity was 335 mm total length whereas the size at which 95% of females reached sexual maturity was 398 mm total length. The average size at which 50% of the females had inverted to the male condition was found to be 678 mm total length. The range of sizes at which the process of sexual inversion took place was broad, between 428 and 725 mm total length. The reproductive period was long, almost covering the annual cycle, although the maximum activity was observed between April and October, with a peak in spawning in June-July.

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.

Reproductive biology of Boops boops (Linnaeus, 1758) off Gran Canaria (Canary Islands): a preliminary study

[EN] Preliminary data of the length-weight relationship and reproduction of the bogue Boops boops off Gran Canaria (Canary Islands, Central-east Atlantic) are provided. Two thousand and twenty-one individuals of bogue, ranging from 4 to 34 cm TL, were obtained from purse seine commercial landing. Reproduction parameters as sex determination, duration of spawning season, size at first maturity and GSI variation along time were determinated based on macroscopic evaluation of gonads. The results obtained suggest that bogue is a total spawner, with a long spawning season extending from January to May. Size at first maturity was 16.7 and 17.9 cm TL for males and females, respectively. The length-weight relationship obtained showed a positive allometry in both sexes

Estancia en el ICM-CSIC de Barcelona con Eunicella sp

[EN] Verano 2013, Barcelona. Experiencia personal en la investigación de la nueva especie de gorgonia descubierta que habita en la zona profunda del Cap de Creus. Investigación en su reproductividad mediante estudios asociados a sus gónadas y pólipos...