My uncle had an easy fix to this crowding problem. This is going back to the 70's when gun laws had a few grey areas. He would set up his rod on the ice or shore, then he would walk about 20 yards out and put his " brown bottle " on the ice / shore. Then when the weekend warriors showed up and tried to squeeze in close to where he was fishing out comes the shotgun and BAM, BAM, BAM. Then he would ask if his target practice was bothering them
. They always left while the next three shells were being loaded.
Dodger.