Reproductive traits and seasonal variations in the spawning activity of female albacore, Thunnus alalunga, in the subtropical western North Pacific Ocean

To clarify the reproductive activity of albacore, Thunnus alalunga, in the subtropical western North Pacific Ocean (WNPO) (13–25°N, 133°E–171°W), reproductive traits, such as the sex ratio, spawning season, batch fecundity, size at maturity and spawning fraction, were investigated. The sex ratio (5 cm intervals) was skewed towards females in each fork length class less than 95 cm and was skewed towards males in each fork length class larger than...