Mitochondrial DNA (mtDNA) polymorphism in the essentially non-anadromous River Usk brown trout Salmo trutta population was investigated by restriction analysis. Following mtDNA extraction and purification on caesium chloride density gradients, monomorphic restriction profiles were obtained with HaeIII, HindIII...
It was for an engraved stone which would be lovingly released into the river Usk, which is where my fly fishing adventure began. And it will be post lockdown and I hope to witness it but may not be able to. Eventually someone may pick up this (my) stone from the bed of the river...