ECASA WP 2
Friday, 17 December 2004
Annotated sheet for indicators1
related to the impact of aquaculture on the environmenti
1- Name of indicator, authors
Accumulation of heavy metals in sediment
Dean, R.J.
From sams
2- Computation: Formulae, or model output.
Whenever possible, please use a range of 0-100. Ranking the results in few classes (five?) is
another option for qualitative indicators.
Use of sediment heavy metal concentrations to characterise impacts.
3- List of data / parameters required for computation.
Actual sediment heavy metal concentrations. Requires ICP-MS analysis of sediment samples
4- Description of scientific meaning, references
Of the metals present in fish farm sediments, elevated concentrations of copper and
zinc have been reported in Scotland and Canada. The principal sources of these metals are
antifoulant paints and fish feed. Additionally, cadmium, molybdenum and uranium are
enriched in fish farm sediments, and up to 150 m away from farms. Metal concentrations have
been shown to increase over the farm growing season. Redox-sensitive metals may be subject
to sediment horizon migration due to increased organic enrichment from farm activities.
References:
Ankley, G.T. , DiToro, D.M., Hansen, D.J., & Berry, W.J., 1996. Assessing the ecological
risk of metals in sediments. Environmental Toxicology and Chemistry 15, 2053-2055.
Brooks, K.M. and Mahnken, C.V.W., 2003. Interactions of Atlantic salmon in the Pacific
Northwest environment III. Accumulation of zinc and copper Fisheries Research 62, 295–
305.
Dean, R.J., 2005. Physical and biogeochemical pathways of metals around fish farms. Ph.D.
thesis, UHI Millenium Institute/Scottish Association for Marine Science.
Smith, J.N., Yeats, P.A. and Milligan, T.G., in press. Sediment geochronologies for fish farm
contaminants in Lime Kiln Bay, Bay of Fundy. In: B.T. Hargrave (ed) Environmental
effects of marine finfish aquaculture. The Handbook Of Environmental Chemistry (vol. 5):
Water Pollution. Springer Verlag.
Yeats, P.A., Milligan, T.G., Sutherland, T.F., Robinson, S.M.C., Smith, J.A., Lawton, P. and
Levings, C.D., in press. Lithium normalised zinc and copper concentrations in sediments
as measures of trace metal enrichment due to salmon aquaculture. In: B.T. Hargrave (ed)
Environmental effects of marine finfish aquaculture. The Handbook Of Environmental
Chemistry (vol. 5): Water Pollution. Springer Verlag.
1
Please return these sheets to the WP 2 leader, BEFORE end of March 2005.
5- Range of validity; please provide a description of the field of validity for the
indicator, its limits, endpoints. Careful explanations should be given in a table
about the correspondence between the computed values and the impact (from
positive effect, no impact , moderate impact, high impact, unacceptable impact).
Certain regulators (SEPA) already issue acceptable standards of sediment metal
concentrations. A range of theses values up to the EQS can be calculated/tabulated.
6 -Type of aquaculture on which this indicator applies
ALL
7 - Relevant environments for this indicator
MOST soft-bottom environments where sediment sampling is easiest, although sediment traps
may be deployed in hard substrate areas to at least establish metal concentrations in waste
food/faeces.
8- Quotation. We will need to select the most appropriate indicators to be proposed for
EIA and site selection. Please suggest a quotation for this indicator for the following
criteria (from A, perfectly adequate, to E, not relevant), to help evaluating the
indicator within WP 4. Additional comments are welcome.
 Direct relevance to objectives :
–A–
 Clarity in design : It is important that the selected indicators are defined clearly in
order to avoid confusion in their development or interpretation. – A - Well established

Realistic collection or development costs : Indicators must be practical and realistic,
and their cost of collection and development therefore need to be considered. This
may lead to trade-offs between the information content of various indicators and the
cost of collecting them. – B - Main limitation is the cost of sediment heavy metal
analysis.

High quality and reliability : Indicators, and the information they provide, are only
as good as the data from which they are derived. – A – These analyses are robust and
reliable, subject to quality control between laboratories.

Appropriate spatial and temporal scale : Careful thought should be given to the
appropriate spatial and temporal scale of indicators. – A – Well tested along spatial
and temporal gradients, subject to several post-graduate studies.

Obvious significance : The meaning and usefulness of the indicator should easily be
understood by stakeholders. B –
9- Data and models related to this indicator, available for use by WP 4. Please list the
data and models output available at local, national or regional scales for use by ECASA.
They may not correspond to the more theoretical list asked for in §3.
Existing datasets from numerous Scottish fish farm studies held at SAMS, and Mediterranean
sites investigated during MERAMED
10- Suggestions for use by WP 5. Give examples of indicators/aquaculture/environments
which can be field-tested during the course of WP 5.
All environments and aquaculture types can be assessed using these indicators.
0.1 m-2 van Veen grab or similar taking grabs along an organic gradient with samples
taken at reference stations. Possible use of sediment traps in hard substrate areas.
This document is intended to be used for internal work on ECASA workpackage. The final
indicator sheet may include a format somewhat different. Please suggest any improvement for
both the content and the form of this document.
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