Not saying that the fish don't adapt. Just that I noticed a change in the location of the bait. ICM could actually still see the fish moving past him and could not get them to take.I always thought that reds were very adaptable to salinity change, here's why. I am a native Floridian and spent the majority of my time fishing the St Johns River. The St Johns River flows South to North. I fished the Orange Park area all my life where the water was considered brackish.
During several bass tournaments I would hook reds as far south as Green Cove Springs. That said we would also shrimp from a dock in Green Cove Springs and fill the coolers. Occasionally someone would hook up with a flounder that far south. The water had to be less than brackish and more fresh water in that area as the St Johns River is a spring fed river.
I can also remember a huge bull shark being caught off a dock in Orange Park but I suppose that's not so rare.
Maybe in that area of Florida the fish just learn to adapt?