Overfishing Trends in a Swimming Crab Population in a Small-scale Fishing Ground, Chonburi Province

Abstract

    The assessment of overfishing is a challenge because it is a complicated and time consuming process. Nevertheless, knowledge of the types of overfishing that occur in a fishery is valuable information for management. This study proposed a short-term and simple approach to identifying trends and types of overfishing in a data limited situation. Collectively, the results indicate that the fishery under study is trending towards overfishing because the proportion of the immature individuals in the catch has reached around 68%. Furthermore, the results show that male and female crabs had different forms of overfishing. Whereas the female swimming crabs were at risk of ‘recruitment overfishing’, the male crabs were experiencing ‘growth overfishing’. Moreover, the results suggest that mesh size regulation may not be appropriate for successful management because it is inconsistent with the nature of fishing practices. The catches from the fishery comprise mainly immature fish. If larger mesh size regulation were enforced, the yields could be drastically reduced to as low as 36.50% of the usual catch. Such restrictions could result in the failure of the fishery and its management because the fishers would likely not abide by them. Seasonal fishing closures are potentially appropriate. A closure needs to be short and applied at the times and places that will benefit the crabs that are susceptible to overfishing. Given the situation where fishers are made aware of the fishery’s resource crisis, closure regulations could possibly be accepted.