Sturgeon in the Great Lakes

Excerpt from The Dynamic Great Lakes "The largest and most primitive fish in the Great Lakes is the Sturgeon. Cruising along on bottoms of the lakes, they remind us of dinosaurs that roamed planet Earth in earlier epochs. Their huge bodies are supported by cartilage as well as bone. They can weigh up to 300 pounds, and like some dinosaurs, they have rows of plates along their heads and bodies to protect them. When all of the lakes and their tributary rivers were cleaner than they are now, and when there were no dams to block their way, these great fish would spawn by running up rivers. In Lake Superior, they still run up the Sturgeon River in Michigan’s Upper Peninsula to spawn and may be seen surfacing like submarines, sticking their snouts above the water in pools below waterfalls. The Sturgeon has been living in the Great Lakes ever since the last glaciers retreated and fish entered the lakes through crystal clear tributary streams. Sturgeon’s eggs (roe) are a delicacy known as caviar when processed for human food. In 1974 the Sturgeon was included on a list of threatened species. These ancient fish cruise the lake bottom feeding upon crayfish, insect larvae, clams and bottom plants. This is their ecological niche where they use their long shovel shaped snout with a sucker-like mouth underneath to feed. Two whisker-like barbels near their mouths help them to feel their way along the bottom. The Sturgeon is slow to mature; it may not spawn until it is 14 to 22 years old."