SHIOCTON, Wis.-Swollen by spring rain, the river is the color of strong tea. It runs high and fast, sliding between walls of trees that are still naked and gray. In some places, it spills over its banks and floods the woods. Lloyd and Jane Merkel balance on some rocks and peer down into the water.
"Isn't she a beauty?" Jane Merkel says as a gray fish the length of a man swims past, its big tail making slow undulations. Fish appear and disappear, rising out of the deep water to nuzzle the rocks at the edge of the river, coming singly and in bunches of six or eight, splashing in the shallow water. They have spiky backs, bristly snouts and mouths like vacuum cleaners.
They are sturgeons, and they have transformed the Merkels into volunteer conservationists who have driven two hours from their home in southern Wisconsin to guard them.
Sturgeons are struggling to survive in much of the world, from the Caspian Sea to the Chesapeake Bay to the Missouri River. But here, in eastern Wisconsin, they are thriving. Each year, thousands of them swim from Lake Winnebago, where they spend most of their lives, up the Wolf River to spawn, creating a spectacle that biologists say occurs no place else.
When word gets out that the sturgeon are spawning, fanciers converge on the Wolf. Many, like the Merkels, volunteer to guard the spawning grounds, standing 12-hour shifts to discourage poachers while the fish lay their eggs at the river's edge.
Sturgeons are among the oldest fish on the continent. They evolved in the Cretaceous period, about 100 million years ago, and they look it. Most are big; some are immense. The lake sturgeon, which lives in the Mississippi River, the Great Lakes and Canada, is a middling sturgeon. It grows to more than six feet and well over 100 pounds. Like other sturgeons, it lives a long time. In 1953, a lake sturgeon caught in Lake of the Woods, in Ontario, measured 81 inches long and weighed 215 pounds. It was 152 years old.
It had been a fingerling during Thomas Jefferson's administration.
Eight species of sturgeon live in U.S. waters. Four are endangered and another is threatened; all are watched closely by scientists and conservationists. Sturgeons cannot be easily brought back from the brink. Unlike other fish, they mature late and reproduce slowly. Female lake sturgeon might not reproduce until they are 25 years old; after that, they spawn only every other year. Sturgeons in the Great Lakes have never recovered from heavy fishing in the late 1800s and early 1900s.
"Once you tip them over the edge and over-exploit them, stopping the fishing isn't going to bring them back automatically," says Ron Bruch, a sturgeon expert with the Wisconsin Department of Natural Resources. "The few remnant stocks left in the Great Lakes are very small and scattered. We have not had significant commercial fishing for 100 years, and populations are just now beginning to increase to where we can catch a fish now and then. It's taken that long."
Sturgeons are survivors. They live a largely hidden life, snuffling along the bottom of lakes and rivers and eating almost anything they bump into. As Fred Binkowski, a senior scientist at the Great Lakes Water Institute, likes to say, "Whatever killed the dinosaurs didn't kill sturgeons."
But since the 19th century, sturgeons have declined almost everywhere. The recent collapse of the Caspian Sea sturgeon, the source of most of the world's caviar, is only the best-known example.
Recent years have seen increasing efforts not just to save the sturgeon but to restore it to waters where it has vanished. In 1984, biologists began taking eggs from Wisconsin lake sturgeon and releasing the fry into the Missouri and Mississippi rivers, where natural populations had almost disappeared.
When the Tennessee Aquarium in Knoxville went looking for a conservation project a few years ago, it seized upon the sturgeon. The aquarium is releasing fish - raised from Wisconsin eggs - into the Tennessee River, hoping to re-establish self-sustaining populations.
Atlantic and shortnose sturgeon once abounded in the Chesapeake Bay; today they are rarely found. David Secor, a sturgeon expert at the Chesapeake Biological Laboratory, doubts they will ever return to the bay in significant numbers. Humans have simply altered the surrounding land so much that the bay can no longer support sturgeon. Farming has flooded it with nutrients that deplete oxygen in warm weather. Thick silt covers spawning areas.
"I've become rather pessimistic," Secor says. "We can't go back to water quality as it was in the 19th century. I think it's reasonable to strive for, but I don't think we're going to get there."
A more recent threat to North American sturgeon is the appetite for caviar. With less caviar coming from the Caspian Sea, the industry has turned increasingly to America, especially to the shovelnose sturgeon, a small sturgeon that lives in the Mississippi River. In the past half-decade, fishermen have been netting the shovelnose in unprecedented numbers, and their numbers have plummeted. In Missouri alone, fishermen increased their catch of shovelnose sturgeon 10-fold from 1998 to 2001. Some states have banned fishing for shovelnose sturgeon; others are considering it.
In a few places, sturgeons have been nursed back to abundance. Shortnose sturgeon are thriving again in the upper Hudson River, thanks to a cleaner river. The number of sturgeon in eastern Wisconsin has increased five-fold since the 1950s. Tougher game laws have helped, but so has a profound change in public attitude, as well as hundreds of thousands of dollars contributed by sporting groups to improve spawning grounds.
Nowhere is the change in attitude more apparent than in Shiocton, a river town of 954 people on a bend of the Wolf River. Only a few decades ago, the people of Shiocton were notorious as poachers and scofflaws. Young men took pride in outwitting local wardens.
"It was a game of cat-and-mouse," says Dick Suprise, 56, co-owner of Dick and Jeanni's Family Restaurant. He acknowledges having poached an occasional sturgeon himself. But not any more. "I haven't done it for 35 years," he says. "It isn't the thing to do."
Today, sturgeons are a tourist attraction. Each year, hundreds of people gather at Bamboo Bend, just outside Shiocton, to gawk at them. "I've always wanted to come out here," says Al Alder, an insurance agent from Little Chute, Wis., who had brought his 10-year-old daughter, Chrissy. Up and down the bank, parents and children lean over the water's edge in wonder.
Just a few miles away, volunteers assemble at the "sturgeon camp," a converted farmhouse. The sturgeon patrol started 28 years ago to help out overwhelmed game wardens. Today it attracts more than 400 volunteers each year. Not everyone gets to go out, but 18 or more people might be on the river at any one time, watching over some of the 56 spawning areas.
Todd Schaller, a warden dubbed "sturgeon general" for the week, briefs volunteers and hands out cell phones. "You're just a visual deterrent," he tells one couple. "If you see someone, don't confront them. Just call us. But the fact that you're here - there shouldn't be a problem."
The Merkels drive down a dirt road until it ends at the river. It's a quiet, lonely place, and for the next 12 hours they see only a few fishermen passing in boats.
"It was gorgeous," Jane Merkel says after sitting with the sturgeons until dawn.