Modeling the effectiveness of holding cages and Thai-style hatcheries in Philippines blue swimming crab fisheries and their economic viability

Abstract:

Fisheries are an important aspect of global food production, but for many, such as the blue swimming crab (Portunus pelagicus) fishery in the Philippines, stock abundance has dropped significantly due to over harvesting. Many strategies exist to manage fisheries, and one such method to mitigate the effects of overharvesting is to allow gravid female crabs to release their larvae before processing the crabs. This strategy can be implemented through placing females in holding cages to allow for spawning or to rear the eggs in Thai-style hatcheries. However, the efficacy of larval release to mitigate the effects of overharvesting has not yet been measured. In this report, a theoretical population model was constructed as a first step in estimating the efficiency of these release methods. The model tracks the survival of a cohort of released crab larvae both in the planktonic and benthic phase.