Marine pen fish farming: Charging changes

We are proposing three programmes of work designed to deliver the sea lice regulatory framework’s monitoring strategy. This section provides an overview of the proposed work. More detail is provided in annex 1.2.  

Juvenile salmonid population assessment 

We use electrofishing of rivers to assess the impacts of human pressures upon fish populations and to monitor trends in population health (improvements or deterioration). 

We have a small team of fish biologists who undertake this work across Scotland. Over 2024, we allocated all our resources on sampling west coast rivers draining into Wild Salmon Protection Zones in which modelling indicates risk to wild salmon post-smolts may be relatively high. 

We will maintain some of our electrofishing resources on the west coast and northern isles and will focus monitoring on those catchments where there are a range of predicted pressures.  

Our charges to regulated businesses are currently insufficient to recover the cost of resourcing monitoring required under the sea lice regulatory framework. We propose to contract out electrofishing surveys to deliver the monitoring network determined by us in consultation with key interest groups.   

Sea trout lice monitoring 

We intend to introduce a sea trout netting programme which will help us assess the impact of sea lice from fish farms on sea trout. This will replace the current programme of netting which is funded by a combination of Scottish Government, and marine fish farm operators.   

We will design this national sea trout monitoring programme in consultation with key interest groups. The programme will cover the West Coast, Western Isles and the Northern Isles. We don't have the capabilities to deliver this type of monitoring, and we consequently plan to contract this work out.  

Sentinel cage monitoring  

We are working with fish farmers and other interested parties to develop a programme of monitoring to assess and validate the performance of sea lice dispersion models at predicting the concentrations of infective-stage sea lice in wild salmon protection zones. The monitoring involves placing small numbers of farmed salmon in sentinel pens within a wild salmon protection zone for short periods and then counting the number of sea lice that have attached to the fish. This will allow us to assess whether sea lice loads of fish in sentinel cages are consistent with concentrations of lice predicted from our sea lice models. Differences in the relative levels of sea lice found are compared with modelled concentrations of infective-stage sea lice predicted around each pen over the period of sentinel pen deployment. 

We don't have the capability to deliver this type of monitoring. We consider that fish farm operators are best able to deliver it. Consequently, so long as the operators carry out the monitoring programme according to plans agreed by us (following consultation with other key interested parties) we do not intend to charge for this work. We have included an audit process in our projections (see Annex 1.4). We do recognise that sentinel cage monitoring will represent an increase in costs for operators. 

Other resource demands  

We will also need additional resources to provide for the ongoing management of the monitoring programmes and the analysis and interpretation of the data.