Keeping the big fish: Economic and ecological tradeoffs in size-based fisheries management

We explore several issues raised by a size dependent regulation of a fishery in a situation where it is important for conservation purposes to keep highly reproductive big fish and where the fish prices depend on their body size. Firstly, we represent in a common modeling frame, the interplay between the biological characteristics of the exploited species (growth, reproduction) and the price/size relationship. Secondly, we explore the benefits of conservation measures based on a maximum body size for the fish caught instead of a minimum body size. As a result of computations, it appears that one should ask whether a management based on a maximum body size is not both possible to implement and equally protective of the stock, even when the price function depends on the size of fish.