Reproductive timing and reproductive capacity of the Skipjack Tuna (Katsuwonus pelamis) in the western Indian Ocean

Mean size at maturity (L50) for female skipjack tuna in the western Indian Ocean is estimated between 39.9 cm and 42.0 cm FL.

“Mean size at maturity, i.e., length at which 50% of female skipjack tuna are classed as mature (L50), has been estimated at between 39.9 cm and 42.0 cm FL in the western Indian Ocean (Stéquert, 1976; Grande et al., 2014).”

In the western Indian Ocean, skipjack tuna has a higher mean relative batch fecundity (140.0±64.0 oocyte g-1 of gonad-free weight) than yellowfin (74.4 oocyte g-1) and bigeye (11.5±7.1 oocyte g-1).

“Studies carried out in the western Indian Ocean show that skipjack tuna has a higher mean relative batch fecundity, 140.0±64.0 oocyte g -1 of gonad-free weight (Grande et al., 2014), than yellowfin, 74.4 oocyte g -1 of gonad-free weight (Zudaire et al., 2013a), and bigeye tuna, 11.5±7.1 oocyte g -1 of gonad-free fish (Zudaire et al., 2016).”

In the western Indian Ocean, spawning of skipjack tuna occurs throughout the year, with peaks of intensity between November-March and June-July, coinciding with the northeastern and southwestern monsoon periods respectively.

“In the western Indian Ocean, spawning of skipjack tuna occurs throughout the year, with peaks of intensity between November-March and June-July, coinciding with the northeastern and southwestern monsoon period respectively (Stéquert et al., 2001; Grande et al., 2014).”