ALEXANDRIA, Minn. – Piece by piece, information continues to be gathered to solve the mystery of the Lake Victoria bison bones.
While bones found at the site on the east edge of Alexandria more than four years ago are being studied at Hamline University in St. Paul, soil samples were just taken last weekend for additional study.
Kate Pound, geology professor at St. Cloud State University and five students visited the Alexandria lake Saturday to take core samples from the lake bottom.
"I read about it and it intrigued me," Pound said of what is believed to be a historic bison kill site. "I thought if we can do a core that might answer some questions, that would be a good thing!"
Pound said the samples could show the history of deposits in the lake, which could show where the sediment came from and provide a record of human settlement.
She said the core "could show a distinct change of when the land was cleared and more sediment went into the lake."
She said researchers would also look for shells, bones, artifacts, charcoal and other things in the sample that may offer historic information about the site.
One of the students, Jen Wyers of Minnetonka, an earth science major at St. Cloud State, selected the bison kill site as her senior research project.
"I've always been interested in archaeology, and this whole process intrigued me," she said.
Also on hand as the core samples were taken was Roger Van Surksum, the Alexandria fisherman who found the first bone at the site in 2011.
"I never thought I would get any interest in archaeology," Van Surksum said in a previous interview. "I thought I was just a walleye fisherman."
The first bone was found on June 14, 2011, when Van Surksum, a fishing guide, was testing a walleye fishing spot on Lake Victoria.
Instead of pulling a walleye from the water, he pulled out a bone, black as coal, about 10 inches long.
He searched the Internet and asked around to see if he could figure out what the bone was.
Divers Wayne Wagner of Brandon and Wesley Torgrimson of Evansville agreed to join Van Surksum in hunting for more bones or other artifacts at the site, which was marked using a GPS system.
The men dove at the site three times during July and August of that year, coming up with more than 200 bones, including an upper and lower jaw bone, neck bones, vertebrae, pelvis and a bison's horn.
The quest for answers
Van Surksum drove some of the bones to St. Cloud State, where experts informed him they were similar to those of the Great Plains bison, and were possibly anywhere from 200 to 10,000 or more years old.
Van Surksum was referred to David Mather, the Minnesota Historical Society's National Register archeologist, who traveled to Alexandria in September 2011 to examine the bones.
Mather said the large quantity of bones in one spot signified the remains of a Native American kill site, where bison were killed and processed for food, tools and weaponry.
The bison might have been forced over a nearby cliff to their deaths. The bones showed evidence of cut marks or breaks possibly made by humans during the butchering.
Radiocarbon dating would bring more information about the age of the bones, but the results could be skewed by 500 to 600 years because of the effects of the water.
Mather said he believed the bones were between 200 and 6,000 years old and classified them as modern bison.
The men were asked to stop diving until an archeological team could be assembled. The site was registered as an official archeological site. Future study may include underwater excavations and an archeological dig on the nearby land.
Two years later, on Oct. 25, 2013, students and faculty from Hamline University in St. Paul came to get the bones for further study.
Associate Professor Brian Hoffman said the anthropology department is attempting to find out how long ago the bison were alive and how the remains wound up in the lake.
The research includes radiocarbon dating, a process that uses the decay of radioactive isotopes to discover the age of organic materials.
Many unknowns remain
"This has been driving me crazy," Van Surksum said of waiting for answers. "It all takes a lot of time, but I'm anxious to know the story behind this."
While the students and professor gathered the core samples, Van Surksum and his friends put an underwater camera down in other spots in the area.
When the bones were first found and the initial dives conducted, the water was murky and visibility was poor.
The lake has since been infested with zebra mussels, which aggressively clean up particles from the water, leaving it clear. They also attach themselves to hard surfaces.
In spots where a camera was dropped down, objects too numerous to count were seen along the sandy bottom.
"Those are all bones," Van Surksum said. "I'm sure of it!"
Until he hears news from the researchers and the experts to confirm what he already believes to be true, the fisherman will continue to share the story of his biggest - or at least the most unique - catch of his career.