Scientific name: Acipenser fulvescens
- One of the oldest species in the Great Lakes
- Currently threatened and rare due to overharvest and habitat loss
- Grow very slowly but may reach 8 feet long and 300 pounds
- Can live for 55-150 years
Lake sturgeon are nearshore fish that live at water depths of 15-30 feet. They feed along lake bottoms, eating a variety of small animals including snails, crustaceans, aquatic insects, mussels, and small fish. Most lake sturgeon caught today weigh between 30-100 pounds and grow to 3-6 feet in length.
Lake sturgeon live longer than any other fish species in Michigan. Male lake sturgeon live an average of 55 years. Females live 80-150 years. Despite their long lives, sturgeon are slow to mature. It takes about 15 years for male lake sturgeon to reach reproductive maturity and 20-25 years for females.
In early spring, adult sturgeon enter fast-flowing rivers to spawn. Female lake sturgeon spawn once every four years, each depositing million of eggs on gravel bars. It is estimated that only about 10-20 percent of adult lake sturgeon within a population spawn during a given year.
Human use and misuse
Lake sturgeon were historically abundant in all of the Great Lakes. They served as an important food source for many Native American tribes. When European settlers arrived in the region, sturgeon were so numerous during the spring spawning run that they were reportedly capable of capsizing fishing boats.
Early commercial fishermen scorned sturgeon as nuisance fish that destroyed their gill nets. A single thrashing sturgeon could tangle an entire net, reducing opportunities to catch valuable lake whitefish or lake trout. People began to catch the less desirable sturgeon and destroy them in large numbers. They burned huge piles of sturgeon along the shores of the Detroit River. The oily sturgeon carcasses provided fuel for passing steam ships.
By the mid 1800s, people had found profitable uses for sturgeon. They harvested sturgeon for their meat as well as their eggs, which were made into a flavorful delicacy similar to caviar. Sturgeon swim bladders were processed to produce isinglass, a type of gelatin used in making beer and wine. Lake sturgeon became a commercially valuable resource that was soon overharvested. In 1880, more than 4 million pounds of sturgeon were processed in Michigan, taken from Lake Huron and Lake St. Clair. By 1928, the total sturgeon harvest from all the Great Lakes fell to less than 2,000 pounds.
In addition to commercial fishing, the remaining sturgeon population faced a growing number of threats. Newly constructed dams blocked access to river spawning habitat. Other spawning locations were destroyed by sedimentation from farming and logging and increased industrial pollution. These changes, combined with the sturgeon’s slow growth, led to its dramatic decline. The current lake sturgeon population is estimated to be 1 percent of its historical abundance in Michigan.
Habitat restoration and recovery
Michigan now prohibits commercial fishing for lake sturgeon and closely regulates sturgeon sport fishing. A limited number of sportfishing licences are issued each year. In some areas of the state, volunteers help monitor spring spawning runs to protect sturgeon from being taken illegally. Other management efforts focus on tracking sturgeon migration and identifying the location of remaining spawning grounds. Restoration efforts involve creating and protecting sturgeon habitat to enhance spawning success.