The reproductive biology of the rainbow runner, Elagatis bipinnulata (Quoy & Gaimard, 1825) caught in the São Pedro and São Paulo Archipelago

Abstract

The rainbow runner, Elagatis bipinnulata, which belongs to the Carangidae family, has a circumtropical distribution. It is found throughout the Atlantic Ocean, from Massachusetts (USA) to Bahia (Brazil). The reproductive biology of the rainbow runner was studied, using specimens captured off the São Pedro and São Paulo Archipelago. From July 1999 to November 2003, a total of 352 fishes were analysed (201 females and 151 males). Fork length (FL) was measured and specimens were gutted for gonads collection. In the laboratory, gonads length, width and weight were measured, and sexes identified macroscopically. Through histological analysis, five different maturation stages were identified for females: immature, maturing, mature, spent and resting. A predominance of maturing and mature females was observed from January to May. The highest gonad index (GI) values were also observed during this period, ranging from 7.7 to 55. Mean sexual maturity size (L50) for females was estimated at 64.6 cm (FL). In the studied area the species exhibited total spawning, with two synchronous groups. Testicles were histologically very similar making them impossible to differentiate sexual maturation stages. Considerable variation was observed in the male gonads weight, hampering the assessment of size at maturity. However, GI values for males were also higher from January to May. These results suggest that the spawning period of the rainbow runner in the São Pedro and São Paulo Archipelago occurs during the first semester of the year.

Reproductive biology of dolphinfish, <em>Coryphaena hippurus</em> (Actinopterygii: Coryphaenidae), in Saint Peter and Saint Paul Archipelago, Brazil

“…The highest monthly mean values of GI coincided with those of other species in the SPSPA, such as wahoo (Viana et al 2008), rainbow runner (Pinheiro et al 2010) and blackfin tuna (Bezerra et al 2013), which also exhibit a period of increased reproductive activity in the first half of the year, coinciding with the presence of flying fish at the study site. Castro et al (1999) reported values of gonadosomatic index (GSI) with a peak in June for both sexes in the Canary Islands, coinciding with the summer in that region.…”

Whale Shark (Rhincodon typus) Seasonal Occurrence, Abundance and Demographic Structure in the Mid-Equatorial Atlantic Ocean

“…Water temperature is known to induce fish reproduction/spawning events [70–72]. Fish reproduction studies conducted in ASPSP have indicated spawning periods of several species mainly between January and June [30,73–76]. The abundant sally lightfoot crab ( Grapsus grapsus ) reproduces in ASPSP during the whole year, but largest abundances of ovigerous females were observed from December to May [77].…”

Influence of upwelling on the availability and frequency of pruning of Elagatis bipinnulata (Roy & Gaimard, 1825) landed by the Ivorian maritime artisanal fishery

“…Elagatis bipinnulata , is a species of fish that belongs to the family Carangidae and the genus bipinnulata. Also known as Rainbow Runner or Banana Fish (local name), this large migrant is one of the pelagic fish found in the warm tropical and temperate waters of all continents 1 . It is a fish highly appreciated by the population, which justifies its great commercial value.…”

“…Making this activity profitable generates precise knowledge of the abundance periods of the species during the year. These moments of high concentration would favor the catches, since the swiftness of this fish to swim 1 is an impact on his productivity. Previous studies have focused on biology and diet, respectively in Brazil 1 and in Colombia 2 .…”