) throughout the coast was also obtained , and the proportion of their revenue that comes from selling canned fish was estimated. These estimates were pooled to obtain the total number of people employed per ton of seafood in the local markets. Peruvians, and foreign markets were considered end consumers in the study, and these did therefore not include employment or cost of operation. Similarly, rural farmers, other sectors,
and the national food security program, El Programa Nacional de Asistencia Alimentaria (Pronaa), were also considered end consumers, and there is therefore no account of the derived benefits from the use of selleck chemical fish products from these groups, including of the employment they provide. Cost structures were reconstructed
from structured interviews of key stakeholders involved with each step of the value chain. Some cost structures for the industrial anchoveta fleet were updated and developed based on estimates in De la Puente et al.  and calculations for the artisanal fleet were updated based on estimates in Estrella et al. , Alfaro-Shigueto et al. ; Estrella and Swartzman . The majority of the cost estimates, however, came from interviews and fieldwork that were undertaken as part of the present study. Included import taxes for materials (e.g., tin cans) were not considered, nor were value added taxes in the costs. This is to some extent countered by not considering the export subsidies that enterprises may get to compensate for the import taxes they have paid. The contribution of the fisheries sector to the Gross Domestic Product (GDP) of Peru was estimated based Birinapant on the income approach  by evaluating the following sum for each enterprise type in the fisheries sector as well as for each seafood commodity, equation(1) GDP=Ce+Ip+Ct+Co–IsGDP=Ce+Ip+Ct+Co–Iswhere Ce is the total cost of compensations, Ip is the gross operating profit, Ct is total taxes, Co cost for management, royalties, certification, and monitoring, and Is
is the income from subsidies. The value chain module used here is coupled with the Ecopath and Ecosim (EwE) modeling framework, but does not rely on the EwE Tau-protein kinase models for parameterization  apart from obtaining the landings and fleet structure from the underlying Ecopath model (and these could in principle be entered independently of the Ecopath model). All other information that was needed to develop the value chain analysis as presented in this contribution was thus derived independently of the underlying ecosystem model. The coupling with the EwE models, however, enables evaluation of the full value chain analysis as part of mass-balance modeling , time-dynamic simulations , policy optimizations , spatial optimizations , management strategy evaluations, and other analysis where social and economic factors are considered.