Seasonal Cycles of Biting Bugs
Isle Royale’s climate is kept at a cooler temperature than the surrounding mainland by the cold water temperatures of Lake Superior. A cooler climate alters the length and warmth of summer seasons and shortens the activity time of all insects including mosquitoes and black flies. These species tend to hatch around late May into early June. Typically, they are worse in late June and early July. By late August and early September, insect numbers typically decline.
Prepare For Biting Insects
Size: 0.125 – 0.3125 inches (3 - 8 mm)
Size: Approximately 0.12 inches (2-5 mm)
American Horse Fly
Size: Approximately 0.3 inches (8 mm)
Size: Approximately 3/16 inch.
Last updated: April 15, 2022