To learn more about the requirements for Benthic Impacts, watch the presentation narrated by Javier Unibazo, Head of Standards.
If you want to read more about the specific indicators/requirements regarding this topic [Criterion 2.6: Maintaining benthic ecosystem structure and function] and other information relating to the ‘Alignment’ and draft ASC Farm Standard (including specific questions part of the Stakeholder Survey), please click here.
These issues are also currently addressed within the existing ASC species Standards: all of ASC’s 11-species Standards can be found here.
Why is this an issue?
Discharge from aquaculture production systems usually contains organic material (e.g. faeces, uneaten feed) and on some cases heavy metals (i.e. copper from treated nets). Although the manner of discharge can vary (dispersed vs point-source), all have the potential to negatively impact the structure and function of the local ecosystem, especially the seabed. High levels of copper – for instance – becomes toxic to the benthic fauna.
The extent of impact depends on the amount and type of the material that is released, the characteristics of the water body and the local capacity for natural decomposition. If managed well, the amount of discharge can be kept within the rate of natural decomposition, thereby minimising benthic impacts.
Contact person: Javier Unibazo
Key considerations regarding the proposed revisions of the benthic requirements
A Technical Working Group (TWG) was formed to revise the current approach to benthic impacts in the ASC Standards and recommend revised Criterion/Indicators based on the latest scientific knowledge and current best practices within the aquaculture industry.
The objective of this revision is to define Criteria/Indicators that collectively address the benthic impacts of aquaculture in all major production systems that discharge into different water types.
The scope of the revision is on the following six aspects:
- Types of benthic indicators and limits
- Timing of monitoring sampling
- Frequency of monitoring sampling
- Allowable zone of effects (AZE)
- Location and number of monitoring sampling
- Third-party assessment/Testing methods/Accreditation.
To date, the TWG has developed draft recommendations for a revised indicator on benthic impacts requirements for marine cages. These recommendations are based on a three-tiered sampling approach and acceptable limits established for abiotic and biotic parameters measured at different distances from the cages.