On a mission to rescue a 'dinosaur'

She’s never eaten them, didn’t even know they existed in Wisconsin and admits they have “a face only a mother could love.”

But naturalist and citizen science manager Mary Holleback has developed a passion for saving lake sturgeon and is even on call to help restore water flow in their tank when the power goes out at Riveredge Nature Center in the Town of Saukville.

Holleback has been with Riveredge since its main building was constructed 35 years ago, and she’s been a leader of the Milwaukee River Lake Sturgeon Rehabilitation Program at the center since its inception 20 years ago.

“As a kid I never even had a goldfish, so it’s a big stretch to start with,” she said.

The longtime educator turned student and did some research into the biggest and oldest freshwater fish.

“Right there should tell      you something about their importance,” Holleback said.

Sturgeon go so far back that they’ve been found in dinosaurs’ stomachs.

“They are considered dinosaurs. They predate the Great Lakes,” Holleback said.

They were wiped out. Overfishing during the Great Depression, pollution and dams eliminated natural reproducing sturgeon before efforts began to restore their population in Lake Michigan.

“Back in the day, people didn’t realize you could fish them to death,” Holleback said.

Sturgeon remain an endangered or threatened species in 19 states. Only in Wisconsin are they on the less-serious watch list.

Holleback said multiple groups watch for illegal harvesting. If fishermen catch one by accident, they must release it.

Sturgeon don’t have many natural predators. When they’re small, great blue heron, snapping turtles and big northern bass can eat them, but sturgeon grow quickly and are prickly, Holleback said.

Grants from multiple agencies, led by the Wisconsin Department of Natural Resources, kick-started the rehabilitation initiative, and it went through early growing pains.

The first year the eggs developed fungus and only 27 sturgeon were released.

Research from other facilities doing the same work improved methods. Riveredge now uses hatching cones, then hatching jars and maintains a constant flow of water for fresh oxygen and to prevent fungus.

The fish get moved to a fry tank, then a fingerling tank at Riveredge’s streamside rearing facility.

Several are in an aquarium near the entrance of Riveredge’s main building that will stay there until fall. They come to the surface seeking food when people approach. At night, their eyes have a golden glow that makes them look like fireflies, Holleback said.

Groups across the country working to restore the sturgeon’s population visit the Shawano Dam on the Wolf River in spring to capture eggs during spawning. The eggs are fertilized on the spot and put in hatching jars at Riveredge.

When the fish spawn depends on the weather. It has to be 55 degrees. A group from Georgia comes every year and stays from days to a week or longer to wait for the spawn.

Regardless of timing, it’s an event, Holleback said. Many come to watch.

“It’s a little bit of a circus, actually,” she said.

Results of the effort outlasted many of its volunteers. It takes 20 to 25 years for female sturgeon to mature. The fish can live for more than 100 years, with females reaching six to eight feet and males four feet.

Riveredge alone released 632 fish on Sept. 27, and this was the first year a sturgeon from the project’s first release was found in an Ozaukee County waterway. A tag on the fish showed that it was the same one that a 3-year-old from Thiensville, whose mother is director of the Mequon Nature Preserve, released into the water. That child has since graduated from high school and is serving in the military.

More fish have been found from Riveredge’s sturgeon project, but that was the only one from the first release.

“The volunteers are overjoyed. At least three have been here for 20 years. It’s fun for all of them to see success. They can see the value of the work they put in,” Holleback said.

Her passion for nature started long before her sturgeon efforts.

Holleback grew up in Wauwatosa feeding birds and watching them during walks with her father. She camped with Girl Scouts and climbed trees with her brother. Her family always had a dog, and she had a turtle, a parakeet and a canary.

She earned a bachelor’s degree in conservation biology and a master’s degree in curriculum and instruction. She taught for a few years at a parochial school in Hartford and volunteered at Riveredge before joining the center full time in 1995.

Holleback has been in charge of the Bluebird Trail, a conservation effort and bird-watching path, helps with bird banding and has led educational programs for children and adults, and at universities.

Holleback prefers to work with birds and plants.

“Not so much fish, but I’ve come to love the sturgeon,” she said.

When she’s not working in nature at Riveredge, she’s doing the same at her home in West Bend.  She gardens, walks her dog and watches birds eat out of what she calls her “squirrel feeders.”

She instilled an interest in nature into her two grown daughters, and her passion to inspire children to appreciate and preserve the natural world persists.

“They have to learn to love it before they can take care of it,” she said.

For more information on the sturgeon rehabilitation program, visit https://riveredgenaturecenter.org/program/sturgeon-fest/#return-the-stur....