Mating behaviour and gamete release in gilthead seabream (Sparus aurata, Linnaeus 1758) held in captivity

Abstract

The present study aimed to describe the reproductive behaviour of gilthead seabream (Sparus aurata) in captivity. Twenty-four mature gilthead seabream, divided in two tanks, were utilized for the present study. Reproductive behaviour was recorded using submersibles cameras. A total of 67 spawning events were analysed. The mean duration time that gilthead seabream spent spawning was 54 ± 4 min/day, during which mean number of individual spawning events was 5.6 ± 0.2. The mean volume of eggs produced by both broodstocks was 405 ± 13.4 mL with a fertilization rate of 91.6 ± 0.4%. The reproductive behaviour began with a schooling behaviour and then forming light aggregations. From an aggregation or an encounter while swimming freely a female initiated a spawning rush followed by one or more males to gametes liberation. The spawning rush was brief, 1.6 ± 0.5 sec, over an approximately 1.7 ± 0.2 m distance from the tank bottom to the water surface. Pair spawning, between a single female and male, was the most common (71.6%). Group spawning was less common and involved a single female spawning with two males (22.5%) or three males (4.9%). Spawning rushes involving more than one female were not observed. Gilthead seabream in the present study presented a tendency to pair spawn and eggs collected as a "spawn" were actually the sum of many separate spawning events over a short time period. This is the first description of gilthead seabream spawning and the findings help to understand microsatellite based observations of spawning kinetics. Additional key words: mate selection; pair group mass spawning; rush; aggregation Citation: Ibarra-Zatarain, Z.; Duncan, N. (2015). Mating behaviour and gamete release in gilthead seabream (Sparus aurata,

Reproductive success of a marine teleost was correlated with proactive and reactive stress‐coping styles

“…subordination) and may have evolved from similarly long‐term to permanent behavioural, morphological, physiological and environmental adaptations. In the case of S. aurata , Ibarra‐Zatarain and Duncan () observed a certain degree of dominance during the courtship and spawning rush. Therefore, when considering possible hierarchies developed by proactive S. aurata during spawning, reactive breeders were thought to implement these alternative reproductive tactics to increase their reproductive opportunities, to reduce their energetic cost and physical risk ( i.e ., injuries).…”

“…(), juveniles of this species present defined proactive and reactive coping styles, but to date, no studies have been conducted on S. aurata breeders. Additionally, Ibarra‐Zatarain and Duncan () described the courtship and spawning behaviour of this species and reported that S. aurata showed a preference to spawn in pairs, which indicates how reproductive hierarchies that dominate contributions to progeny are established and maintained. In this sense, the present study aimed to consider whether and how S. aurata reproductive success is linked with stress‐coping styles.…”

Reproductive ethogram and mate selection in captive wild Senegalese sole (Solea senegalensis)

“…It would appear that spawning in groups is uncommon in flatfish compared to round fish. Spawning in groups of one female with two or more males is common in round fish (Domeier & Colin, 1997) such as gilthead seabream (Sparus aurata) (Ibarra-Zatarain & Duncan, 2015). As was observed in the other eight flatfish species that spawned in pairs the Senegalese sole formed the pair on the bottom and swam up through the water column in synchrony.…”

“…The winter flounder was the exception and was described to release gametes in both a pair and a group (Breder, 1922;Stoner et al, 1999). The gamete release in a group consisted of a single female spawning with two or more males, which is a common spawning behaviour in round fish species (Domeier & Colin, 1997;Ibarra-Zatarain & Duncan, 2015). The eight species that spawned as a pair formed a pair on the bottom before making an upward synchronised coupled swim to release gametes.…”

Early assessment of gilthead sea bream (Sparus aurata ) spawning dynamics by mini-broodstocks

“…Initially, the removal of embryonated eggs at a developmental stage prior to the minimum required stage could be understood as a bias that would result in the removal of all those families from parental matings that occurred only a few hours before collection. However, as the daily egg production in gilthead sea bream generally tends to be concentrated in a short space of time (Ibarra‐Zatarain & Duncan, ), the number of excluded embryonated eggs within each daily spawning analysed was not significant (<5%). Therefore, there is no evidence that the requirement of a minimum stage of development caused any bias in the spawning dynamics established for each daily spawning analysed.…”