1037 Sustainable Maritime Transportation and Exploitation of Sea Resources – Rizzuto & Guedes Soares (eds) © 2012 Taylor & Francis Group, London, ISBN 978-0-415-62081-9 Fuel efficiency in trawlers under different fishing tactics using a consumption model and VMS data: A case-study for the Portuguese fleet A. Campos, T. Pilar-Fonseca, J. Parente & P. Fonseca INRB, IP/IPIMAR, Lisboa, Portugal M. Afonso-Dias Centro de Investigação Marinha e Ambiental, Universidade do Algarve, Faro, Portugal ABSTRACT: Trawling is the most fuel-intensive fishing activity, with trawlers constituting the fleet seg- ment most affected by the high volatility of the fuel prices. This is likely to be a main driver for adopting fuel consumption reduction strategies, which may be related to alternative fishing practices. In this study, individual vessel trajectories obtained from Vessel Monitoring System (VMS) data processed by GIS software (GeoCrust 2.0) are used to characterize a number of operational and economical parameters, for different landing profiles, corresponding to fishing trip types with specific landings composition. This information is combined with fuel consumption estimates derived from a mathematical model for the dis- tinct phases of a round fishing trip, providing an insight into the profitability of fishing operations. Keywords: trawl fleet, Vessel Monitoring Systems (VMS), fuel consumption, economic efficiency, Portuguese waters resolution data provided by the satellite-based Vessel Monitoring Systems (VMS), which col- lect observations on single vessels operation and may provide detailed effort on a highly disaggre- gated spatial scale. The data can then be related to landings revenues and running costs (i.e., the costs depending on vessel specific effort alloca- tion in time and space, such as fuel costs), provid- ing information on vessel profitability. Taking this information into account, fuel efficiency may be tackled, for instance by adopting the best running point, that is, the vessel’s operating speed, both in trawling and in free navigation, that maximizes net income. The Portuguese VMS (MONICAP), is pres- ently operating in vessels with Length Overall (LOA) higher than 15 m (EC, 2003), including all coastal trawlers, fishing in Western Iberian waters, ICES division IXa. Global Positioning System (GPS) data for each vessel, consisting of a suc- cession of geographical locations (latitude, lon- gitude), dates, times and speed, are received on board, recorded and automatically transmitted via satellite (Loran-C) to the Portuguese Fisheries Directorate (DGPA/IGP), the national monitor- ing authority responsible for marine surveillance. The frequency of data transmission is at present 1 INTRODUCTION The significant amount of time spent during trawling and navigating among fishing grounds, place bottom trawlers among the most fuel- demanding coastal fishing vessels. Energy saving in trawlers has been a subject of research since the 1970’s oil crisis, leading to several studies aimed at improving vessel design and power consumption. As an example, special attention has been given to hull resistance (Kasper, 1983) and gains in propul- sive efficiency (Basañez, 1975, O’Dogherty et al., 1981, Haimov et al., 2010). Parente et al. (2008) addressed the economy of energy in Portuguese coastal trawlers by looking at trawl gear perform- ance and the operational procedures along the dif- ferent phases of the round trip. Potential increases in the Net Cash Flow (NCF) of up to 27% over the range of operational navigation and trawling speeds were achieved through gear modifications (Parente et al., 2008) Information on vessel activity (including geo- referenced data) on a trip level is of utmost impor- tance for understanding fleet strategies in fishing effort allocation and contributing to the design of efficient energy management solutions. This is now possible due to the existence of high spatial