| This study aimed to fill information gaps in opelu fishery biology and life history as well as catalogue fisher knowledge and the socioeconomics of the opelu fishery in West Hawaii. Field sampling and laboratory analysis examined the biological characteristics of opelu caught by two different fishing methods including size, growth rate, age, sex ratio, maturity, spawning condition, and feeding ecology. Fisher interviews contextualized biological data as well as documented fishery data. Decapterus macarellus (Cuvier 1833) comprised 98% of the total catch while Decapterus macrosoma (Bleeker 1951) composed 2%. The opelu hoopnet fishery catches significantly smaller (mean SL 227.49 +/- 28.7mm) and more immature fish (78%) than the handline fishery (284.25 +/- 25.7 mm, 7.5% immature). D. macarellus are primarily noctural feeders with a diet comprising of 82% crustacean zooplankton by weight. D. macarellus exhibited an ontogenetic diet shift indicated by deltaN15 and deltaC 13 stable isotope analysis. |
