Reproductive patterns of blacktail comber (Serranus atricauda, Serranidae) from south-west Portugal seamounts

Abstract

The knowledge of the reproductive strategy is essential for the comprehensive understanding of the population dynamics of any fish species. This study intends to define the spawning season, verify the type of fecundity regulation and estimate relative annual fecundity for Serranus atricauda inhabiting the south-west of Portugal seamounts (Gorringe, Ampère and Lion). Monthly samples, between September 2010 and December 2011, were obtained from commercial vessels. This species is synchronously hermaphroditic, and mature individuals were found all year round, with gonadosomatic index peak from February to September. No clear relation between hepatosomatic index and Fulton's condition factor and gonadal development was found, and therefore, it is probable that reproductive success depends more on environmental conditions and food availability during the spawning season than on body energy reserves. No gap exists between pre-vitellogenic and vitellogenic oocytes and the oocyte size-frequency distribution during the main spawning season show no dominant cohort progressing through time. The number of standing stock of advanced vitellogenic oocytes showed an increase trend along the spawning season decreasing only at its end and the relative intensity of a-atresia was always low throughout this period with an increase towards the end. All these criteria corroborate the indeterminate fecundity type assigned to S. atricauda in previous studies. Mean relative annual fecundity estimated was 5,655 ± 4,321 oocytes per gram of gutted weight.

Diplectrum radiale (Quoy & Gaimard, 1824) (Serranidae): A rare case of simultaneous hermaphroditism in a teleost fish

“…However, the values of RBF found in this study were close to those reported by Alós, Alonso‐Fernández, Catalán, Palmer, and Lowerre‐Brabieri () and Neves et al. () for the simultaneous hermaphrodites S. scriba (mean of 83 hydrated oocytes/g) and S. atricauda (mean of 22 hydrated oocytes/g), respectively.…”

“…Similar results have been reported for other hermaphrodite species such as D. formosum by Obando and León (), Serranus scriba by Tuset et al. () and S. atricauda by Neves, Sequeira, Paiva, Vieira, and Gordo ().…”

Reproductive strategies of the marine fishes from the southwest Atlantic Ocean: an application of histological and image processing techniques

“…This relative low production might be related to the spawning frequency of this species that must be high to compensate the low number of hydrated oocytes produced. However, the values of RBF found in this study were close to those reported by Alós et al (2013) and Neves et al (2014) Fecundity is also affected by the fish size, weight and condition, being the key parameters to assess fecundity at the population level (KJESBU et al, 1991;. Thus, the RBF was negatively affected by all factors measured, revealing that the smaller specimens with a better condition produce more hydrated oocytes per gram of body.…”

“…This type of ovarian organisation is typical of multiple spawning species with a very protracted spawning Obando and León (1989), Serranus scriba by Tuset et al (2005) and S. atricauda by Neves et al (2014). Multiple spawning fishes with indeterminate fecundity usually produce large batches of hydrated oocytes (GANIAS et al, 2004;GRANDE et al, 2014;GARCÍA-SEOANE et al, 2014).…”

“…So far, the model-based stereology is the most common procedure to estimate the number of oocytes in fish (GANIAS et al, 2014). This includes oocytes in primary growth, vitellogenesis and atresia, as well as post-ovulatory follicles (ISAAC-NAHUM et al, 1988;GREER WALKER et al, 1994;WÖHLER, 1994;BROMLEY et al, 2000;COWARD;BROMAGE, 2002;MEDINA et al, 2002;COOPER et al, 2005;MEDINA et al, 2007;ALONSO-FERNÁNDEZ et al, 2008;SABER et al, 2011;HASLOB et al, 2013;GARCÍA-SEOANE et al, 2014;KNAPP et al, 2014;NEVES et al, 2014;VILLEGAS-RÍOS et al, 2014). Although, it should not be used to count cells of irregular shape and/or highly variable size, e.g.…”