Although a limited number of these collapses may have been caused or exacerbated by natural phenomena (for example, climate variability), human activities and overfishing - essentially non-sustainable management - are the primary culprits (Pauly et al., It is important to understand that fish constitute not only biomass in the ocean but a potential economic input into society. Together, these two elements imply that fisheries are an economic activity by which fishers can catch fish resources in perpetuity if they are managed sustainably.