Social and ecological dynamics of small-scale fisheries in the context of rapid globalization.

摘要

Tropical small-scale fisheries are understudied and the social and ecological feedbacks are poorly understood; yet they are one of the most economically valuable systems in terms of ecosystem services, generate half of the global fish supply and employ the vast majority of the world's fishers. They are typically found in remote areas at the margins of markets, economic development and government services. However, increasing globalization and connectivity to international markets can result in profound and complex changes to the local economy, livelihoods, resources and the fundamental social norms that govern harvest practices.;Social networks mediate large-scale change and shifts in social norms. Previous research has shown that networks are important in shaping institutional management of resources. Yet these studies measured structural characteristics of networks at the communal level. This dissertation builds on this foundation by examining the impact of social networks on individual behavior. Specifically, it looks at two main research questions: First, in the context of rapid globalization, what factors explain changes in fishermen's harvest and management behavior? Second, what have been the effects of market access on a remote, small-scale fishery?;I conducted interviews to measure the effect of social networks on changes in three social norms in four different communities: (i) fisherman's catch and release practice, (ii) enforcement of sea tenure and (iii) seasonal use of gill nets. In addition, I conducted fisheries independent assessments of the lagoon fishery to determine changes in length-frequency, mean trophic level, and relative biomass as the fishery progressed from primarily subsistence to primarily commercial harvest over the last two decades.;I found that social networks have an influence on fishermen's catch and release behavior, enforcement of sea tenure and seasonal use of gill nets. In addition to social networks, I also found that change in personal gear investment and recent harvest rates explained some of the variation in catch and release practice. Fishermen's age and food security also influenced fishermen's enforcement behavior.;In assessing the impact of harvest on the fishery, I found that there were significant declines in all fishery indicators measured at the community and species level: mean trophic level, mean length and relative biomass. The economic impact of declines in fish abundance are important to note. Decline in biomass of the most economically important species, snook Centropomus undecimalis, translates to an estimated 75% decline in fishermen's income from snook over time.;Markets can deliver important economic benefits to small-scale fishers of the developing world, yet rapid globalization and connectivity to markets in the presence of weak governance systems may exceed communities' ability to adapt and fail to deliver expected economic promises in the long-term. This can result in a cycle of poverty for vulnerable fishermen who have access to few, if any, other income-generating opportunities. This research contributes to the conservation of small-scale fisheries by assessing the impact of harvest as a result of commercialization and improving understanding of the actions of those most integral to the sustainability of the system-fishermen.