| Resumo: |
Several attributes of populations of sedentary organisms differentiate benthic fisheries from those approached by the classic theory, inspired by fin-fisheries. The assessment and management of sedentary resources require the application of non-conventional methodological tools. Understanding the fishing process, in particular, is central to the analysis and management of those fisheries. The purpose of this thesis was to investigate the fishing process and its impact on stocks of the Patagonian scallop (Zygochlamys patagonica) fishery. Data and information utilized included: (i) historical data from commercial vessels and experimental fishing; (ii) positional, catch and effort data, and additional information corresponding to fleet activity between 1995 and 2005; (iii) interviews to fishermen; and (iv) information from surveys of abundance. After introducing the fishery (Chapter 1), the macro-scale distribution of the populations and the spatial correspondence between three main fishing grounds and frontal systems in the Argentine Shelf (SW Atlantic) are described (Chapter 2). Lower-scale spatial units, 'fishing opportunities' (FOs), were identified using positional trawl data (Chapter 3). Finally, the key components of the fishing process at different spatial scales were investigated: (i) fishermen decisions, particularly the decision of leaving a FO which is being fished (Chapter 4); (ii) spatial patterns of allocation of fishing effort; and (iii) trends in catch per unit effort (CPUE) as a consequence of abundance and the spatial allocation of fishing effort (Chapter 5)
Universidad Nacional del Comahue. Centro Regional Bariloche (Argentina)
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