The lake is home to various fish species, including Brook Trout and Cutthroat Trout. Nearby activities include hiking, camping, and bird-watching. To catch fish at Lake Isabelle, it is recommended to use small lures or flies. The best time to visit is from May to October when the weather is pleasant, with average temperatures ranging from 60°F to 70°F. Visitors should come prepared for changing weather conditions and be aware of potential trail closures due to snow or wildlife activity.