Would the shape/size of either of your bays allow the use of blocking nets? It sounds as though you may be somewhat lacking in larger [forage]size gills, though total numbers are ok...perhaps you could "squeeze the tube" by raising forage size over the early spring/summer, feeding behind a net, getting your gills to 4-6", where they might be more optimal for your larger predators. You might put some larger gills behind the nets as well, and raise them past easy pickins for the northerns.