Summer line fishing. In summer many fishermen fish using a float line, sinker-float, and other methods. Line fishing is one of the most popular methods, when you can fish from a boat or a bank using a light and resilient fishing rod. This method is widely used to fish for roaches, breams, perches, and other freshwater fishes. The stamp shows summer-time fishing from a boat and a river-bank, as well as the fishing equipment.