Sea-Run Brown I believe are like SRCs. SRCs, and SR Bull Trout for that matter, only spend around 3-4 months in the salt water before heading into the rivers/creeks starting in June through November. They then spawn in December - April. Run timings are very different and widespread between river systems. Durring their time in the rivers they are actively feeding on salmon eggs/flesh, October Caddis flies, nymphs, and anything else they get in their mouths. They are also very aggressive, and very fun on the fly rod since they will hammer flies. There are exceptions as you can find a few SRCs in the salt durring mid-winter and their months in the salt water can varry. Sometimes they won't even migrate to the salt if they find a good food source one year in the river (or they will delay their migration).

I cannot say for sure if SRBs are like SRCs. But I have seen on tv people fishing for them in Argentina and they where using nymphs and such and cating them.