Water quality requirements for marine fish cage site selection in Tenerife (Canary Islands): predictive modelling and analysis using GIS

Site selection is a key factor in any aquaculture operation, affecting both success and sustainability. The correct choice of site in any aquatic farming operation is vitally important since it can greatly influence economic viability by determining capital outlay, and, by affecting running costs, rates of productions and mortality factors. It is impractical to try control water quality parameters in cage culture systems, therefore culture of any species must be established in geographical regions having adequate water quality and exchange. This study used GIS and related technology to build a spatial database using those water quality variables which were considered to have an influence in developing marine fish-cage culture of seabass and seabream in Tenerife (Canary Islands). The water quality variables identified were: temperature, turbidity (runoff soil erosion and sewage), disease stress (sewage) and possibility of waste feedback from fish-cages (bathymetry). Variables were grouped in a logical model and combined to generate outputs showing the most suitable areas for siting cage culture. Most areas of the coastline of Tenerife were identified as being suitable or very suitable, and none was identified as totally unsuitable. Sensitivity to parameter changes was tested in order to evaluate the model, by changing one parameter at a time. Values chosen were F 5%, 10% and 15% of the reference 0044-8486/02/$ see front matter D 2002 Elsevier Science B.V. All rights reserved. doi:10.1016/S0044-8486(02)00274-0 * Corresponding author. Investigaciones y Servicious Marinos (INSEMAR), San Clemente 14/5j, S/C de Tenerife 38003, Spain. Tel.: +44-1786-473-171; fax: +44-1786-472-133. E-mail address: [email protected] (O.M. Pérez). www.elsevier.com/locate/aqua-online Aquaculture 224 (2003) 51–68 situation. This analysis shows that the model was especially sensitive to sea temperature and suspended solids. D 2002 Elsevier Science B.V. All rights reserved.