Faced with multiple threats, Atlantic Salmon require this genetic insurance policy should stocks become so low that stocking with genetically distinct natal stocks becomes a requirement. This project mimics the live salmon gene banks that have been established for many years in other Atlantic salmon countries such as Norway and Canada.
Wild parr and smolts are trapped and taken into Drimsallie Hatchery near Glenfinnan from the donor rivers and grown on in captivity to adult maturity using targeted marine diets and specialist rearing techniques. Drimsallie Hatchery operate the largest wild adult salmon captive rearing facility in the UK today. Each river stock is marked and kept in separate rearing tanks (and in some cases there are now more indigenous adults in these tanks than exist in the rivers themselves).
A parallel process, undertaken by the Lochaber Fisheries Trust and UHI Inverness, takes juvenile genetic samples from the rivers and, from analysing these samples, identifies the current estimated wild spawning population present in the river. This informs the requirements (or not) for stocking the river using the live gene bank adults. Should stocking be required then the options are to restock using eyed ova from the adults in captivity, or stock out the adults themselves during the spawning period in order that they spawn themselves in the wild (known as Smolt to Adult Supplementation).
