Sturgeon: Special Report (Part 2 of 2)

When people the world over need advice on how to restore struggling sturgeon populations, they look to Wisconsin.

The state’s largest inland lake-Lake Winnebago-and its connecting waters are home to the largest and healthiest population of lake sturgeon in North America, thanks to a longstanding program of management, enforcement, public involvement, and research efforts headquartered right in Milwaukee.

An ancient species that looks the part with its bony plated armor and shark-like tail, the sturgeon first appeared in the fossil record 150 million years ago during the age of the dinosaurs. It survived the dinosaurs’ extinction.

But in just the last 150 years, human actions have eliminated the durable sturgeon from some waters, and dramatically reduced its populations in others.

Millions of sturgeon once swam the Great Lakes, and others flourished in the region’s inland waters. But European settlers who commercially fished the Great Lakes in the mid-1800s viewed the sturgeon as a net-destroying nuisance to be exterminated.

“They hauled the fish out and threw them on shore to die,” said Fred Binkowski, Great Lakes WATER Institute senior scientist. “Sturgeon were stacked on beaches like cordwood, and used as fuel on steam freighters.”

Around the 1860s, people realized the fish’s value as a source of meat and caviar. Sturgeon soon became a target of intense harvesting, and the already battered Great Lakes population dwindled to less than 5 percent its original size, said Binkowski. Pollution and dams that blocked access to river spawning grounds also impacted sturgeon populations, and still present challenges today.

A Multi-Pronged Effort

To help control harvests, Wisconsin instituted its first sturgeon fishing regulation, an eight-pound size minimum, in 1903. In 1915, it banned sturgeon fishing entirely. “The ban didn’t do much for the Great Lakes because the horse was out of the barn by then, but it gave other places [like Lake Winnebago] time to recover and avoid the same fate,” said Ron Bruch, a Wisconsin Department of Natural Resources (DNR) sturgeon biologist.

The state reopened sturgeon fisheries on a limited basis during the Depression to provide food relief, and has continued managing them since. Decisions about fishing seasons and size and bag limits are supported by an expanded version of a data collection program that began in the 1940s.

Because of these efforts, some 40,000 adult sturgeon now inhabit the Lake Winnebago system-a fourfold increase from 50 years ago. The population is large enough to support an annual spear-fishing harvest of about 1,200 fish that brings $3.5 million into the local economy. Comparatively, Michigan’s spear fishery supports an annual harvest of only five sturgeon.

In addition to management, law enforcement and public involvement have also contributed to Winnebago’s success. Wisconsin banned sales of sturgeon meat and caviar in 1915 and enforces this ban with strict penalties. And hundreds of citizen volunteers help guard against poaching each spawning season by patrolling spawning sites along the Wolf River. Citizens also founded Sturgeon for Tomorrow, the world’s oldest and largest sturgeon citizen advocacy group, whose fundraising banquets have provided around $750,000 for sturgeon management and research since its inception in 1977.

A final factor in Winnebago’s success has been the information gained from a sturgeon research program begun in 1979 by Binkowski at what is now the WATER Institute. Binkowski’s initial work, done in collaboration with the DNR and Sturgeon for Tomorrow, focused on developing technology for raising sturgeon from eggs. “The idea was to protect against catastrophe in the Winnebago system by having the knowledge and technology to rebuild the population if needed,” said Binkowski.

The work largely involved raising fish in indoor tanks, but for a time in the 1980s, Binkowski also raised fish in outdoor net pens located in a Lake Michigan shoreline pond at the former St. Francis power plant. The project showed that sturgeon could be reared in a controlled, outdoor setting at low cost, but that the fish grew more slowly than those reared indoors because of temperature fluctuations.

Binkowski’s research eventually expanded to also include studies of sturgeon reproduction, behavior, and nutrition. Most recently, he has been using radio and sonic telemetry to track young sturgeon in the Winnebago system.

Toward Future Success

Binkowski said people have come from throughout the country and as far away as China to learn about the Winnebago model and apply it to their own restoration of other sturgeon species. Closer to home, efforts are underway to restore lake sturgeon in other Wisconsin waters, including the Milwaukee River-and from there, Lake Michigan. One project, begun in 2003, focuses on releasing young, hatchery-reared sturgeon into the river each year. In addition, the 1997 removal of Milwaukee’s North Avenue Dam reopened 30 miles of the river to the fish.

Bruch said the Milwaukee River has real promise for restoration, but the outcome of today’s efforts won’t be known for decades because sturgeon are long-lived and slow to reproduce. “If we can get them reestablished in the Milwaukee River, it will be a tremendous accomplishment,” he said. “And the ultimate measure of success is if we can bring them back to the Great Lakes.”

Sturgeon, up close and personal

Can’t get enough of the state’s biggest fish? There are many ways to experience sturgeon in Wisconsin, whether from a river bank or an armchair:

• Discovery World has several sturgeon in its aquariums and touch tank. (discoveryworld.org)
• The IMAX movie Mysteries of the Great Lakes follows Ron Bruch in his sturgeon research and restoration efforts. It plays at the Milwaukee Public Museum through March 19, 2009. (www.mpm.edu/imax/greatlakes)
• The book People of the Sturgeon chronicles the history, cultures, research, and management surrounding sturgeon in the Lake Winnebago system. Coauthored by Ron Bruch, Fred Binkowski, and science writer Kathleen Schmitt Kline, the book is scheduled for release in fall 2009. (winnebagosturgeon.org)
• The sturgeon spearing season on Lake Winnebago begins the second Saturday in February and runs for 16 consecutive days unless the harvest cap is reached. (dnr.wi.gov/fish/seasons/lakesturgeon.htm)
• The sturgeon spawning season in the Lake Winnebago system occurs in late April and early May. Several sites on the Wolf River provide opportunities for public viewing. (dnr.wi.gov/fish/sturgeon/sturgeon_spawning.html)
• Young sturgeon are stocked each October in the Milwaukee River in an ongoing effort to restore the fish to Lake Michigan. Individuals can get involved by sponsoring and releasing one of the fish during the annual Return the Sturgeon event. (riveredgenaturecenter.org)

Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.