ONAWAY — With a resounding slap of forked tail on rubber wetsuit, a big female fish expressed her displeasure with the weighing, measuring, poking, and clipping that disrupted her journey up a northern Michigan river.
For the past 20 years, researchers in wetsuits and diving gear have walked and swam the river for a handful of weeks each spring, scooping up sturgeon spawning in the river’s rushing waters.
Data carefully logged on clipboards by the river’s edge helps researchers protect the species considered threatened in Michigan – a combination of overharvesting, habitat loss, and a slow-moving breeding cycle threatening a creature that can live 100 years and grow longer than a man is tall .
Such expeditions have helped revive the faltering species from about 500 sturgeon in Black Lake two decades ago to an estimated 1,200 today, said Douglas Larson, research assistant for the Michigan State University Black River Sturgeon Facility.
On Wednesday, a team of researchers with cold toes gathered data from 22 sturgeon.
As the large fish nosed their way up the river in search of the perfect spawning spot, researchers moved down the river, equipment and oversized nets at the ready.
Snorkels poked from the water and then disappeared as divers spotted their targets, usually lurking in 8- to 10-foot holes at the bottom of the river.
As divers scour the water for fish, a supply-hauling crew wades through thorny undergrowth, scales vertical hills, and plods through voracious bogs as they follow divers down the river.
Stopping where they find enough flat space to work, the bag crew unloads a massive bag of supplies – tagging guns and scanning wands, vials and super glue, and carefully labeled envelopes where the researchers store fin clippings that open a vault of genetic knowledge about each caught fish.
From the water, divers heft their catches, one at a time, onto shore in their nets to be dangled from a bar held high by researchers — often groaning under the burden — and weighed.
Then, workers slide the unhappy fish onto a slab of wood and measure it, snout to tail.
Back in the water but still held securely, each fish undergoes a quick round of pokes and prods. Handheld wands beep if the fish is carrying a slider of metal saying it was raised in a nearby hatchery or an electronic chip embedded in its back.
Numbers tracked by those electronic tags help researchers build a vast database of the river’s fish.
The sturgeon tagging project, run researchers by Michigan State University, tells the information they need to know to protect the species, said Kim Scribner, professor in the department of fisheries and wildlife at MSU and one of the project’s creators 20 years ago.
“This is quite the office,” said Scribner, stepping between tree trunks along a muddy riverbank on his way to tag fish on Wednesday.
He joins the tagging team for several weeks each summer, enjoying, he said, the “bright eyes and bushy tails” of the young workers often employed to help record sturgeon data.
Wednesday’s team included university students and other young workers from the Upper Peninsula, Minnesota, Nebraska, Tennessee, and Manitoba, all earning an hourly wage to wade a river day after day, gathering information to help save a species.
The group cheered and teased as team member Andrew Julian netted his first sturgeon.
“It’s heavier than you’d think,” he said, tugging the fish through the water.
Larson, trying to extract spawning fluids from a male fish, sympathized with the writhing sturgeon.
“I can appreciate that you want to go,” he told the fish. “But, please wait.”
The researchers exclaimed in disbelief over several enormous fish with no embedded tags. The “new to science” fish — probably never before touched by humans, they said — were among only about 9% of sturgeon in the river not tagged and followed by researchers, Larson said.
As researchers worked, volunteer sturgeon guards — many of them downstaters, happy to spend a few days or a week in the woods to protect a Michigan treasure from poachers — wandered toward the group, eager to catch a glimpse of a sturgeon.
White-bellied and smooth, the once-razor-sharp scutes on their backs worn down by time and the river, the enormous creatures sometimes wriggled or flipped a fin as the humans fussed over them.
News Photo by Julie Riddle Divers head into the Black River near Onway to search for sturgeon on Wednesday.
Mostly, though, the giants lay still, researchers reining in their strength as conducted their studies and then, grinning, lifted each fish for a photo before sliding it back into the water.
Awkwardly long and impossibly heavy, gils flaring a bright red, a female sturgeon flicked her head with impatience as a visitor to the river tried to heft her out of the water.
Oblivious to a friendly rub of her white belly, the fish seemed only to want to get back to the serious business of creating the next generation of sturgeon.
Around her, as she slipped into the water, people in waders collected their gear and got ready to find the next fish.
Julie Riddle can be reached at 989-358-5693 or [email protected] Follow her on Twitter @jriddleX.