Monitoring Aquaculture

Introduction

As has been discussed in the introductory sections of this “toolbox”, aquaculture may exert a variety of impacts on the surrounding environment and there is a clear interest in minimizing these effects. The Water Framework Directive (WFD) establishes the Environmental Quality Standards (EQS) for all water bodies within Europe, and activities that may affect environmental quality must comply with these standards. When an aquaculture concession is granted, this generally follows the preparation and approval of an in-depth Environmental Impact Assessment (EIA). EIAs predict the impact of aquaculture, and in order to assess whether the predictions are correct, we also monitor the environment. If the monitoring shows that the impact predictions are correct, over a given period of time, we may decide to reduce monitoring efforts. One of the classic programs that have incorporated this feedback process of EIA – monitoring – farm adjustment is the Modelling-Ongrowing fish farms-Monitoring (MOM) system (Ervik et al. 1997, Hansen et al. 2001) that was developed for salmon farming in Scandinavian fjords. The MOM concept acknowledges that different marine areas vary in their sensitivity to aquaculture effluents and will thus have different capacities for fish production.

Monitoring assessments traditionally include measurement of: a) physical variables, such as hydrography, weather, water temperature, sediment type, etc.; b) chemical variables, including dissolved oxygen, nutrients, suspended solids, dissolved and particulate organic matter, etc.; and c) biological attributes, e.g. algal pigments, biomass, productivity, abundance, diversity, etc. Whereas comprehensive monitoring of marine environments improves our understanding of the functioning of these systems and thus our ability to predict the response of these waters to anthropogenic perturbations, it is often not necessary to include many of the variables that are monitored. One of the objectives of the ECASA project is to establish a set of indicators of environmental impact with respect to aquaculture that may streamline the monitoring process.

One of the more comprehensive manuscripts that was published in recent years on monitoring of aquaculture is entitled “The scientific principles underlying the monitoring of the environmental impacts of aquaculture” (Fernandes et al. 2001). Although it was published several years ago, this paper illustrates some of the fragmentation that still exists in Europe regarding the environmental objectives that motivate the monitoring.

References

• Ervik, A.; Hansen, P. A.; Aure, J.; Stigebrandt, A.; Johannessen, P.; Jahnsen, T. (1997) Regulating the local environmental impact of intensive marine fish farming I. The concept of the MOM system (Modelling-Ongrowing fish farms-Monitoring). Aquaculture 158, 85-94.
• Fernandes, T.F.; A. Eleftheriou, H. Ackefors, M. Eleftheriou, A. Ervik, A. Sanchez-Mata, T. Scanlon, P. White, S. Cochrane, T. H. Pearson and P. A. Read (2001) The scientific principles underlying the monitoring of the environmental impacts of aquaculture. Journal of Applied Ichthyology. 17 (4): 181-193.
• Hansen, P. K.; Ervik, A.; Schaanning, M.; Johannessen, P.; Aure, J.; Jahnsen, T.; Stigebrandt, A. (2001) Regulating the local environmental impact of intensive marine fish farming II. The monitoring programme in the MOM system (Modelling-Ongrowing fish farms-Monitoring). Aquaculture 194, 75-92.