Conservation of Atlantic salmon - gene banking: principles and considerations

Benefits of gene banking

Gene banking is an increasingly used tool to conserve the genetic integrity and diversity of populations threatened by extirpation. In extremis, where stressors cannot be removed, it might be the best and only option to maintain stocks. Further, a well-planned and effectively carried out banking programme can provide a strategic nationwide conservation of stocks under threat. Until recently, such programmes have been limited by a lack of protocols/capacity. However, more recent developments, especially in cryopreservation methodologies, now enable preservation of samples sufficient for mass fertilization and reestablishment of stocks (Bøe et al. 2021) at cost effective rates (especially compared to live gene banking alone).

Gene banking, whether live, frozen, or a hybrid of both can be effectively utilised at either relatively small scales (e.g. for brown trout in a region of Italy; Di Iorio et al. 2023) or nationwide (e.g. the Norwegian Gene Bank; Bøe et al. 2021) and can provide an effective method for preserving the genetic profile of native populations in threatened aquatic species, including salmonids (Goswami et al. 2016, Thipramalai Thangappan et al. 2023). Indeed, where stressors are severe and/or cannot be ameliorated, it may provide the optimum method of conserving a population.