Fresh research from the Game & Wildlife Conservation Trust (GWCT) points to declining survival rates at sea as a key factor in the collapse. The Game & Wildlife Conservation Trust fisheries team electro-fishing to catch and tag salmon parr on the river Frome in Dorset (Image: Game & Wildlife Conservation Trust)Dylan Roberts, head of fisheries at GWCT, said: "We believe declining marine survival is driven by warming seas affecting feeding opportunities for salmon at sea. "We’re also very concerned about the potential high risk of young salmon being accidentally caught in commercial factory fishing nets. "In this context, improving river habitats for salmon is even more crucial. Mr Roberts said: "Without placing greater emphasis on protecting them both at sea and in rivers, we will never reverse their decline."