Movement of spangled emperor (Lethrinus nebulosus) from the waters around the MPA evaluated by tag-and-release method

Abstract

To evaluate the effect of marine protected area (MPA) of spangled emperor Lethrinus nebulosus, tag-and-release method was conducted between 2013 and 2019. In recaptured fishes, the distance travelled of 44 individuals were revealed, and 70% of those individuals were recaptured within one year. In addition, 77% of the individuals that were recaptured after more than one year were recaptured within 10 km from the release point (median 3.3 km). Those results suggested that the home range of L. nebulosus was relatively small. On the other hand, three of 20 mature individuals moved more than 10 km during or just before the spawning season, and two of them were recaptured in a set net off Yomitan Village 43–46 km away. Since those individuals were caught with a large number of L. nebulosus that is presumed to aggregate for spawning, those individuals may travel long distances for spawning. This study carried out the tag-and-release method on wild L. nebulosus and clarified migration and growth of this species. This study shows that the MPA is effective for protecting sedentary-young L. nebulosus and has spillover effect to the sea areas that are relatively distant from the MPA.