Sea lice management in marine-based salmon farming: Public perceptions and acceptance in England and Scotland

Abstract

Marine-based salmon farming faces a significant challenge in the management of sea lice infestations, particularly in high-density production areas. Multiple strategies have been employed on salmon farms to prevent and treat sea lice infestations, but they have widely varied in their effectiveness in reducing infestations and their associated impact on the marine environment and fish welfare. Typically, cost and effectiveness are crucial considerations for salmon industries and researchers when determining which practice is optimal for reducing sea lice infestations, but the public's views on sea lice management have not yet been fully assessed. Therefore, an online survey was conducted to examine how the English and Scottish public evaluate different sea lice management practices. Participants were randomly assigned to one of eight conditions: four different types of sea lice management practices (medical treatment, mechanical treatment, cleaner fish treatment, or barrier technology) with two types of information formats (basic information or detailed information). The results showed that participants were more accepting of barrier technology and cleaner fish treatment than medical treatment and mechanical treatment, regardless of whether the presented information was basic or detailed. However, providing detailed information about mechanical treatment and cleaner fish treatment negatively affected the participants' acceptance and perceptions compared to the basic information condition. Specifically, when detailed information was provided, mechanical treatment was evaluated as less natural and less welfare friendly for farmed salmon, and the corresponding salmon products were considered to be less healthy than when basic information was provided. Similarly, when detailed information was provided, cleaner fish treatment was rated as less natural, less environmentally friendly, and less welfare friendly for cleaner fish than when only basic information was provided. This study has implications for salmon industries and policymakers: the public encourages a natural way of managing sea lice that has a minimum negative impact on the environment and farmed salmon, which might clash with the current realities of salmon farming.