An ordinary dive in search of old bottles has led to an extraordinary archaeological discovery beneath a Wisconsin lake.
asserted
dive → lead → lake
Mark Schachtner, a diver from Beaver Dam, spotted a partially buried 17-foot dugout canoe while exploring Pewaukee Lake in May.
uncertain
Schachtner → spot → May
Radiocarbon dating has since established that the vessel is about 1,000 years old.
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vessel → establish → ?
According to the Wisconsin Historical Society, the canoe dates to the Late Woodland period and is made of white oak.
uncertain
canoe → accord → oak
The Society is consulting with Native Nations and archaeological experts to document the discovery, while the canoe will remain submerged rather than being removed from the lake.
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canoe → consult → lake
Diver searching for bottles finds an ancient canoe
Schachtner has been diving in southeastern Wisconsin for about a decade and regularly explores lakes with the Four Seasons Dive Club, often looking for old embossed glass bottles.
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Schachtner → search → bottles
During a dive in Pewaukee Lake in early May, however, he noticed what appeared to be a much older object resting on the lake bottom.
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what → notice → bottom
Schachtner told Wisconsin Public Radio (WPR) that the canoe was the oldest human-made object he had ever found.
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he → tell → Radio
He had previously discovered a fossil while diving in another lake, but the canoe represented an entirely different kind of find.
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canoe → discover → find
The vessel was lying about 15 feet beneath the surface and was partially filled with sediment.
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vessel → lie → sediment
Schachtner recognised it as a dugout canoe because he had previously worked with Tamara Thomsen, a maritime archaeologist with the Wisconsin Historical Society who has studied ancient canoes in Wisconsin.
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who → recognise → Wisconsin
Within days of the discovery, Thomsen joined Schachtner at the site.
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Thomsen → join → site
She and the team recorded measurements, photographs and video and collected wood samples for further analysis.
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She → record → analysis
Thomsen described the discovery to WPR as a “beautiful find” and noted that the canoe remained intact on the lake bottom.
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canoe → describe → bottom
Radiocarbon dating places it around 1,000 years ago
The wood was identified as white oak by Michael Wiemann at the U.S. Department of Agriculture's Forest Products Laboratory in Madison.
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wood → place → Madison
The species is also found in several other ancient canoes previously documented in Lake Mendota.
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species → find → Mendota
A sample was then analysed by Beta Analytic, a radiocarbon-dating laboratory in Miami.
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sample → analyse → Miami
The results indicated a 70% probability that the canoe was in use between A.D. 992 and 1049, placing it roughly 1,000 years ago.
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canoe → indicate → it
The period corresponds to Wisconsin's Late Woodland period.
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period → correspond → period
Researchers also found evidence of how the canoe was made.
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canoe → find → evidence
Thomsen told WPR that char marks were visible on its underside, while scraping marks appeared consistent with shaping using stone tools or shells.
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marks → tell → tools
The findings offer clues about the methods used by Indigenous canoe makers during the period.
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findings → offer → period
Mark Schachtner, a diver from Beaver Dam, spotted a partially buried 17-foot dugout canoe while exploring Pewaukee Lake in May (Image Credit: Wisconsin Historical Society)
Why the canoe may have been intentionally submerged
The canoe's condition and position have also provided clues about how it may have been used.
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it → spot → clues
Thomsen told WPR that the way the vessel was sitting in the sediment was characteristic of a canoe that had been deliberately cached.
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that → tell → canoe
According to Thomsen, Indigenous people commonly sank canoes into lakebeds and allowed them to fill with sediment.
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them → accord → sediment
They could later retrieve the vessels, let them dry somewhat and return them to use.
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them → retrieve → use
This practice would have helped preserve and store heavy wooden canoes that were difficult to move over land.
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that → help → land
Larry Plucinski, a tribal historic preservation officer for the Bad River Band of Lake Superior Chippewa, told the Milwaukee Journal Sentinel that dugout canoes were a primary form of transportation during the period and were generally used by the broader community rather than being individually owned.
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canoes → tell → community
He explained that their weight made them difficult to carry over land, making it practical to leave them near the water for later use.
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it → explain → use
Jon Greendeer, president of the Ho-Chunk Nation, told WPR that the discovery falls within Ho-Chunk territory and that he was excited by the find.
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he → tell → find
He also said that finding canoes and other Indigenous artifacts in the area was not unexpected.
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finding → say → area
Greendeer described canoe construction as a labour-intensive process, noting that the vessels were crafted by carving wood using fire and other tools.
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vessels → describe → fire
Canoe will remain underwater
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Canoe → remain → ?
The discovery adds to Wisconsin's growing record of ancient dugout canoes.
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discovery → add → canoes
State archaeologists and volunteers have examined 88 out of 130 known vessels on lake bottoms and within collections across the state, said Thomsen.
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Thomsen → examine → state
Thomsen said Wisconsin has half of the top 10 oldest canoes in eastern North America.
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Wisconsin → say → America
The Pewaukee Lake canoe is actually the second ancient canoe known to have been found there.
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canoe → know → ?
According to Thomsen's research into historical newspaper accounts, another canoe was discovered and removed from the lake in the 1930s.
uncertain
canoe → accord → 1930s
Unlike the previously recovered vessels from Lake Mendota, however, the newly identified canoe is not currently being removed.
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canoe → recover → Mendota
The Wisconsin Historical Society is consulting with Native Nations, including the Ho-Chunk Nation, and the decision is to leave the canoe in place out of respect for Indigenous ancestors.
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decision → consult → ancestors
…and 4 more, not listed.
The Aporia
