Work Package 2

Identifying and quantifying the most relevant indicators

of the interactions of aquaculture on ecosystems

Summary

Our approach to this workpackage will be to research the range of parameters that have been proposed as useful ecosystem indicators of aquaculture interactions and, where appropriate, to propose new indicators.  To be useful for management, indicators should be:

1. Relatively easy to understand by non-scientists and other users

2. Sensitive to a manageable human activity (e.g. aquaculture)

3. Relatively tightly linked in space and time to that activity

4. Easily and accurately measured, with a low error rate

5. Measurable over the area where they may be used

6. Based on existing time-series data to help set objectives

7. Cost-effective

Indicators that pass these initial tests will be presented in an integrated draft document to the partners for comment and input followed by an initial workshop (including experts and representatives from international bodies where they are not already represented within the consortium) to finalise the draft. This provisional list of indicators will then be tested against existing datasets in WP4 in order to determine their utility to the ecosystem approach prior to being tested at a range of field sites (WP5).

Work Package Aims and Objectives in Full

The EEA have carried out a scoping study on indicators for fisheries (EEA Technical Report 87) according with the DPSIR (driving forces-pressure-state-impact-response) assessment framework (EEA, 1999).  The aquaculture releveant indicators are given below along with some comment as to their appropriatness:

Need for water resources: this indicator is not very relevant to mariculture systems per se, although clearly water quality issues are of paramount importance to reared stocks.

Trends in aquaculture production in a given area or volume of water: this indicator could be used when the area is hydodynamically defined (eg a loch, fjord or lagoon). However, it is rather difficult to achieve reliable estimates for open coastal bays with variable levels of assimilative capacity.

Food conversion ratio (FCR): it is a meaningful indicator, since it allows calculation of wastes. However, there is a need to consider that decrease in FCR has a limit (imposed by the physiology of the organisms). This index is not expected to change dramatically unless there are changes in management or technology involved for example in minimising food loses through active feedback systems. FCR alone does not directly indicate environmental effects (assimilative capacity is not taken into account) but rather the profitability of the industry, which is interested in achieving low FCR values for financial reasons. The link of this variable to profitability is in part responsible for the difficulty in obtaining information from operators. 

Total feed used minus aquaculture production: an alternative form of FCR with similar shortcomings.

Sales of chemicals to aquaculture industry: would be a useful indicator of the total release of chemicals as well as of the overall health condition of the industry thereby reflecting the efficiency of the management. However, some member states (e.g. UK) do not currently collect this information centrally. Residues of contaminants in flesh can be used to infer husbandry history and are of critical importance to human health.

Number of escapees per area or length of coastline: there is a problem of arbitrariness in defining coastal length (a fractal variable) and area unless it is a relatively closed system with natural boundaries. Data availability on quantities and on mobility, dispersion ability and survival of the escapees might also be a problem. However, information on the absolute level of escapes regionally is of value considering the issues of genetic interaction that have been shown to have detrimental effects on wild populations (McGinnity et al., 2003). We will establish an explicit link with SSP3 1.3 Task 5 CA “Genetic impact on native populations” to ensure appropriate consideration of such indicators.

Number and total size of fish farms: this is easy to determine but used alone indicates little of environmental impacts since it needs to be complemented with data on site characteristics such as water exchange, depth, management efficiency, etc.

Biodiversity indicators near farms compared with away from farms: there is a reservation on the use of the term "biodiversity" here since it is actually eco-diversity. Reliable monitoring of Biodiversity is still an open issue for research and should involve large spatio-temporal scales, taxconomic capabilities and research effort, unfeasible in the context of monitoring.

Disease incidence: is a good indicator since it indirectly provides integrated information on the overall condition of the industry and the potential for sustainability. It is not necessarily linked to the probability of transfer of disease to wild stocks or other marine species. We will establish an explicit link with SSP3 1.3 Task 4 CA “Potential exchange of pathogens between wild and farmed species” to ensure appropriate consideration of this indicator.

Quality of fish: standards need to be adopted in order to assess quality. These are an important set of indicators relevant to human health, and perhaps animal welfare, although they are only weakly related to environmental effects. However, this indicator has a major influence on the economics of farming owing to the interaction between quality and price.

National legislation with specific provision for environmental management of aquaculture: Legislation on Environmental Impact Assessment is in place in all European countries almost invariably covering aquaculture projects. However, the quality of the statements provided, the techniques/models used for prediction of impacts and the monitoring requirements vary enormously between countries. Additionally, regulation requirements are also variable across the countries covered by the EEA. 

Our approach to this workpackage will be to research the range of parameters that have been proposed as useful ecosystem indicators of aquaculture interactions and, where appropriate, to propose new indicators.  To be useful for management, indicators should be:

1. Relatively easy to understand by non-scientists and other users

2. Sensitive to a manageable human activity (e.g. aquaculture)

3. Relatively tightly linked in space and time to that activity

4. Easily and accurately measured, with a low error rate

5. Measurable over the area where they may be used

6. Based on existing time-series data to help set objectives

7. Cost-effective

Indicators that pass these initial tests will be presented in an integrated draft document to the partners for comment and input followed by an initial workshop (including experts and representatives from international bodies where they are not already represented within the consortium) to finalise the draft. This provisional list of indicators will then be tested against existing datasets in WP4 in order to determine their utility to the ecosystem approach prior to being tested at a range of field sites (WP5).

The socio-economic component of this WP will be conducted within the Driving forces – Pressure – State – Impact - Response (DPSIR) framework for assessing sustainability (EEA Technical Report 87). The aim here will be to develop a typology of indicators that characterise the socio-economic performance of aquaculture, and to highlight the relevance of these indicators to policy-makers. Supplementary objectives will be:

• to trace the links between anthropogenic factors (e.g. increased market demand for aquaculture products) and consequent socio-economic effects (e.g. output, incomes, employment, externalities).
• to identify trade-offs between the various dimensions of performance (e.g. the direct benefits of increased aquaculture production may entail indirect costs due to declining water quality) and to consider the scope for combining separate indicators into a unified measure of ‘sustainability’.

The methodology will rely on secondary data based on published sources, and will assemble information in the following areas:

• Financial and economic performance of aquaculture producers.
• Conflicts between aquaculture and other coastal zone activities e.g. local fisheries.
• Regional multipliers for employment and income.
• External costs of aquaculture (e.g. pollution impacts).

Though the major socio-economic research is described here, there will be integration with other Work Packages.