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This study provides estimates of growth rate, longevity, maturity, spawning seasonality and mortality for Hawai'i's only lethrinid, the humpnose big‐eye bream (known as Mū in Hawai'i) Monotaxis grandoculis, a commercially and recreationally important species in Hawai'i and throughout the Indo‐Pacific. M. grandoculis reaches maturity at 303 mm fork length or 3.6 years of age for both sexes. Males were significantly larger than females for a given age. The von Bertalanffy growth parameters for males and females were L∞ = 506 mm fork length and von Bertalanffy growth coefficient (K) = 0.24 year−1, and L∞ = 427 mm fork length and K = 0.33 year−1, respectively. Both males and females reached ages over 20 years old, with a maximum age of 23 years. M. grandoculis had a distinct spawning season from May through August with corresponding elevated female gonadosomatic index. An age‐based multinomial catch curve indicated that the commercial exploitation rate (natural mortality/fishing mortality) was 0.48 year−1, which is considered below the overfishing limit. [ABSTRACT FROM AUTHOR]

This study provides growth rate, longevity and maturity estimates for the two important species of jack in Hawaiʻi: ulua aukea/giant trevally Caranx ignobilis and omilu/bluefin trevally Caranx melampygus. Maximum observed ages for C. ignobilis and C. melampygus were 31 years and 24 years, respectively. Combined sex von Bertalanffy growth parameter values for C. ignobilis and C. melampygus were as follows: L∞ = 1064 mm and K = 0.18 year−1; and L∞ = 718 mm and K = 0.20 year−1, respectively. Female size at maturity was significantly greater than males for both C. ignobilis and C. melampygus. Size and age at maturity for C. ignobilis was 594 mm and 4.4 years for females and 465 mm and 2.8 years for males. Size and age at maturity for C. melampygus was 372 mm and 4.1 years for females and 329 mm and 2.9 years for males. This study provides the first robust demographic data for both of these highly prized and ecologically important predatory species in Hawaiʻi, which can be used for future assessments or management. [ABSTRACT FROM AUTHOR]