Who is Jim Burden from Stern Men and what is their importance?

Jim, who has experience only as a sternman, finds Ira Pommeroy's buoys floating in his family's fishing territory and sets out to confront him. He ends up in the Mighty J far out in the Atlantic, lost, and out of gas in a terrible storm. Jim radios for help and is told by Ned Wishnell, a premier lobsterman, to drop anchor and wait. Everyone on both islands commences to search. Several hours later Ned finds Jimmy and tries to board the Might J but in heavy seas is dumped overboard and is crushed between the boats and vanishes. This tragedy ends the lobster war of the mid-1950s.