A Bioeconomic Analysis of a Shellfishery: The Effects of Recruitment and Habitat in a Metapopulation Model

Abstract

This paper presents a bioeconomic model wherefishing effort exerted has multiple impacts onthe recruitment process of a sedentaryshellfish population. Recognizing thatsedentary populations generally possessmetapopulation characteristics at therecruitment stage, we show that fishing effortexerted not only influences the recruitmentprocess indirectly by limiting the number ofadults that spawn, but also directly byaffecting the habitat in which shellfish larvaerecruit. Depending on the recruitmentcharacteristics, fishing can have negative andpositive direct and indirect effects on therecruitment process. Next, a positive directeffect that fishing can have on the growth rateof the shellfish population if space to recruitto is limited is studied. Generalcharacteristics of sustainable fishing areanalyzed for the case that recruitment occursimmediately once spawning has occurred as wellas for the case that recruitment takes placeover a longer period of time. Conditions areidentified under which shellfishing should beencouraged in order to facilitate therecruitment process of juveniles. The paperends by analyzing how fishing alters theoptimal sustainable solution when itcontributes to habitat destruction.