Age‐Based Population Dynamics of the Shoemaker Spinefoot Rabbitfish (Siganus sutor) From The Seychelles

Abstract

Spawning aggregations, schooling behaviour and twice-yearly recruitment make the shoemaker spinefoot rabbitfish (Siganus sutor) a major artisanal and subsistence fishery species in the Western Indian Ocean. However, published estimates of its maximum age and growth parameters vary considerably. In this study, we estimate the longevity of S. sutor at 4 years and an asymptotic length of 287.29 mm FL. When analysed by sex, males exhibited a larger L∞ (292.53 mm FL) than females (284.52 mm FL), yet likelihood-ratio tests and confidence ellipses formulated around L∞ and K values indicated no significant sex-based differences in growth profiles. Consistent with previous studies, S. sutor is short-lived, grows rapidly and experiences high mortality yet remains resilient to fishing pressure. However, given its importance to coastal fisheries throughout the Indian Ocean, we recommend a comprehensive, spatially comparative assessment of S. sutor life-history traits and population dynamics across its geographic range. This is necessary to determine whether inconsistencies in age and growth reported in the literature are due to the presence of a species complex with differing growth rates, mortality, behaviour or vulnerability to fishing.