ONAWAY, Mich. — At 6 feet and 100 pounds, the lake sturgeon held by Ed Baker, Kari Dammerman and Nathan Barton was about 80 years old. But instead of roaming the Great Lakes it had been confined in Black Lake behind Alverno Dam its entire life.
The dam was built on the Black River in 1903 during the electrification binge that followed Thomas Edison’s invention of a practical electric light bulb. Fish could go downstream to Lake Huron and Lake Michigan by passing over the dam but couldn’t come back up, limiting the gene pool to the small number in Black Lake.
That limitation, along with further loss of spawning areas and overfishing, led researchers in the 1990s to predict that the Black Lake sturgeon would be extinct within 50 years if something wasn’t done to help them.
Baker, a Department of Natural Resources fisheries research biologist from Marquette, runs lake sturgeon research programs. He brings teams to the Black River each spring to capture fish, take eggs for a hatchery, amass growth and health data and equip sturgeon with tiny transmitters that can be read by scanners.
This wasn’t white-coated lab work. Researchers and volunteers in wet suits and snorkeling gear dove into the deep holes with big hand nets, catching fish and bringing them to shore for a workup.
The volunteer help is provided by Sturgeon for Tomorrow (SFT), people such as Sharon and Bill Church of Herron, who camped for five weeks on the river to watch for poachers and to help new volunteers. Gary Stanaly from Cheboygan is a recreational diver who three years ago showed that by going underwater, he could catch more fish than people in waders.
“They’re usually placid once you get them in the net,” said Stanaly, who has scooped up dozens of the big fish that have roamed the Earth’s waters nearly unchanged for more than 150 million years. “I love this. It’s addictive. I’m lucky I live only a few miles away and can dive here two or three times a week.”
Encountering a 6-foot sturgeon in the dim, ochre light at the bottom of a hole is a marvelous experience. Visibility usually isn’t much more than the length of the fish, and your first impression is that you’ve spotted a downed log as thick as a big man’s thigh.
Then the log sweeps its shark-like tail back and forth and begins to move. But though they look a bit like sharks, sturgeon are harmless. They use their tubular mouth and chin whiskers to find crayfish, clams, mayfly larvae and the odd small fish too slow to get out of the way.
One fish was in a hole where Stanaly, Barton, a DNR research technician from Indian River, and Dammerman, a Michigan State University graduate student, tried for 30 minutes to catch it. They let it settle down for an hour, and on his next trip through the hole Barton surfaced with a huge tail thrashing water from his net.
He towed the fish to the riverbank where it lay docilely as it was sexed (female), measured (6 feet), weighed (100 pounds) and had colored ID tags attached near its tail and a small radio tag inserted hypodermically in a front fin.
Brenda Archambo from Cheboygan, who started the Black River sturgeon guard program 14 years ago, said 350 volunteers had given 3,800 hours to the program this spring and they still need a few more helpers through early June.
Volunteers can work for an afternoon or several days. Some camp for a couple of nights along the river to watch for poachers (who try to spear fish) and sturgeon moving up and down stream.
“The volunteers can really help the collecting teams find where the fish are,” Archambo said. “Poaching is nowhere near what it was before we started the sturgeon guard program, but we did have a few fish killed this year.”
Sturgeon and closely related paddlefish are often called living fossils that evolved before dinosaurs. But there are few real sturgeon fossils because most of their primitive skeleton is soft cartilage like the wiggly end of your nose, rather than hard bone, and it doesn’t fossilize well.
One complete sturgeon fossil was found in the abdominal cavity of a hadrosaurian dinosaur that died 80 million years ago. Since hadrosaurs were vegetarians, paleontologists figure the fish probably was dead or dying when it was swept into the waterlogged carcass of the dead dinosaur.
There are about 28 living sturgeon species, some of which exceed 16 feet and 2,000 pounds. Several others have gone extinct in modern times, and most survivors are threatened or endangered, including lake sturgeon in 19 of the 20 states where they’re found.
The big obstacle in trying to rehabilitate sturgeon is their extremely slow growth. Males don’t mature sexually until they’re about 3 feet long and 15 years old and females at 4-5 feet long and 20-25 years.
Mature females spawn on average once every four years. And though a female might drop 12 million eggs if she spawns 20 times, about 250 of those eggs will survive to be year-old fish.
I like to think that if rehabilitation efforts continue my grandchildren might someday get to fight a 200-pound sturgeon in Michigan. The state record, 7-feet-3 and 193 pounds, was speared in Cheboygan County’s Mullet Lake in 1974.
That was a runt compared with a Lake Erie fish that washed up dead near Buffalo in 1991. It was 321 pounds, and by examining growth rings on its otoliths (ear bones), biologists determined it was 154 years old.
Imagine catching that.
© 2012 the Detroit Free Press