Supermarket statements on salmon farming
As part of the BBC Scotland investigation, Scotland's Fishy Secrets, leading supermarkets were asked whether they took into account any potential lice impacts, from farms, on wild fish when they drew up criteria for "responsibly" farmed salmon.
"We firmly believe that taking great care of the welfare of farmed fish is one of the reasons our quality is so good.
"Alongside this, sustainability and protection of the environment are of paramount importance.
"We buy no seafood on the open market - farmed fish or wild. Long-term working partnerships have been established between us and our farmers. This allows for long-term planning and early adoption of practices that lead to improved quality of fish and sustainability of farming operations."
Select Farm Salmon:
"Waitrose Select Farm Salmon sites are sited in clean, oceanic waters with strong tidal flows.
"Strong tidal sites keep the seabed clean and also help encourage lean and fit fish as they swim in the current, resulting in firmer flesh.
"The term 'responsibly farmed' relates to our strict set of sourcing criteria for farmed fish, with clear and substantiated policies on everything from feed regimes to stocking density and sea-bed management practices.
"We firmly believe that there needs to be clearly defined, industry-wide definitions for fish sourcing standards. It was a lack of such independent standards which led us 15 years ago to launch our own responsible fish sourcing policy.
"We are a founding member of the Sustainable Seafood Coalition - which has the aim of agreeing and implementing industry-wide labelling to provide consumers with accurate information on sustainability."
"Environmental impact is covered in our business wide position and is also covered in the Tesco Farmed Salmon code of practice.
"The code of practice encompasses procedures to ensure that fish welfare and good husbandry are practiced and observed at all times. The issue of sea lice infestation reduction and eradication forms part of this.
"Environmental impact reports must be completed prior to the siting of any fish farm. This is good industry practice and is included in our code of practice.
"We sell a mix of Scottish or Norwegian Farmed Salmon which is clearly identified on the packaging or on the counter ticket.
"'Responsibly farmed' describes the approach we take, and controls that we have in place with our suppliers to ensure the farmed fish we sell meets our standards.
"Our standards are defined within our aquacultural codes of practice and these span environmental concerns, fish welfare as well as the safety and quality of the product. These standards are independently audited."
"We have a well defined code of practice for the production of farmed finfish, including our own label responsibly sourced Scottish farmed salmon.
"We recognise that there could be lice impacts on wild fish but our actions and work with suppliers in this area aim to keep impacts to an absolute minimum.
"Our producers have structured lice treatment plans and we have jointly funded work on new controls designed to further minimise impacts.
"We fully comply with the law with regards to siting of farms which includes provision of detailed environmental impact assessments where appropriate.
"All farms are approved by the local authority, Scottish Environment Protection Agency, the Scottish government - Marine Scotland with guidance from Scottish Natural Heritage."