Numerous man-made “tracks” found in the northern half of Thunder Bay appear similar to anchor drags, but they are often 17 m (56 ft) wide. Some are raised a few meters above the lake bottom.
 Man-made “Tracks”
Image courtesy of Thunder Bay 2010 Expedition, NOAA-OER. Download image (jpg, 50 KB).

Numerous man-made “tracks” found in the northern half of Thunder Bay appear similar to anchor drags, but they are often 17 m (56 ft) wide. Some are raised a few meters above the lake bottom.

Learn more