As far as I know there are no Lake Trout in Island Lake. There are howver hybrid splake which are a sterile cross betwee a brook trout and a lake trout. They can be caught from shore, but are usually found in some of the deeper parts of the lake in areas of 20 ft water depths or deeper. Try some deep running lures or a white tube jig with bait on it fished with a slip bobber. Otherwise the rainbow and brookies are usually susceptible to a fly and bubble set up. Don't forget your long pants, long sleeved shirt and mosquito repellent.