Can you buy Hering the size of your thumb? or more like 3/4 the length?

Where I fish in the summer, I sometimes stay out late (11:00) sometimes just casting and catching nothing and little schools of bait fish will start popping up all around me so I cast into them hopping for a big salmon, and sometimes hook the little guys... they are soooo small, I don't see how the salmon could mistake the herring I use for those little ones.. geuss they also agree bigger is beter :p

- can you use casting nets in area 11? I could pull in a lot of my own right size bait that way