Research Article: Reproductive characteristics of Strombus canarium (Gastropoda: Strombidae) in Samar, Philippines

Strombus canarium or dog conch is an economically important gastropod species for food in many coastal communities in the Philippines. Therefore, there is a need for protective measures to safeguard the stock in the wild. A better understanding of reproductive characteristics is needed to establish a management strategy for the conch fisheries. This study aims to determine the sex ratio, gonadosomatic indices, spawning period, and the relationship between shell length, lip thickness, and gonadal development stage of S. canarium. A total of 212 individuals were collected, of which 71 were male and 141 female. The overall ratio of the population is 1:1.99, of which females dominate in all sampling months. The male dog conch spawned from August to November, with a clear peak in September and October, while the female population has no clear peak. Only three gonadal developmental stages (intermediate, active, and ripe) were observed in both sexes across all sampling months. The correlation analysis indicated that the shell length and lip thickness were reliable indices of sexual maturity for both male and female S. canarium. The information gathered in this study indicates that this species exhibited partial spawning behavior, with complete spawning recorded only in males during specific periods. For fishery management measures, only sexually mature S. canarium with 76 mm shell length should be collected to ensure the individual can reproduce before being harvested.