When archaeological divers discovered a submerged dugout canoe in Wisconsin’s Lake Mendota four years ago, they had little idea that by 2025 they would have found no fewer than 15 more such craft, ranging across 4,500 years of First Nations cultural history.
Their studies have revealed that damaged or sick trees would once have been deliberately picked out for boat-building, and that the canoes had been intended to provide a community service.
After locating and recovering what turned out to be a 1,200-year-old canoe in 2021, as reported at the time on Divernet, Wisconsin Historical Society (WHS) underwater archaeologists continued to work with First Nations bodies to explore Lake Mendota in the state capitol city Madison. The lake covers 40sq km and has an average depth of 12m.
A 3,000-year-old canoe was retrieved in 2022, since when another 14 ancient watercraft have been found, six of them this spring. These were left in situ on the lakebed.
One of the 14 was found through carbon-dating to be 5,200 years old, the oldest ever found in the Great Lakes region of North America, while the most recent was built in the early 1300s AD.
An extended preservation process to stabilise the two recovered canoes is nearing completion, with at least one of them earmarked for display. The US National Park Service has awarded the WHS a $114,000 grant for the work.
Early bioengineering
WHS archaeologist and scuba diver Tamara Thomsen has worked with First Nations of Wisconsin and University of Wisconsin-Madison professor Sissel Schroeder to map and analyse the 16 finds, which were found broadly grouped in two distinct areas.
Thomsen and her dive-team collected timber samples to identify the types of wood and calculate the age of each canoe. Half of the vessels had been built using either red or white oak, according to analysis by the USDA Forest Products Laboratory. This raised questions, because red oak tends to absorb water and is not typically used in boat-building.
The oldest canoe was made of red oak and is thought to have been built around 3,000 BC – the time of the Old Copper Culture in the Great Lakes region and the early Bronze Age elsewhere in the world.
Oaks and some other trees found in the sampled canoes form what are known as tyloses, as part of the ageing process or if they become damaged or infected. These balloon-like cell structures block water movement and prevent fungal and bacterial infections that could cause decay.
“It’s entirely possible that the canoe-builders were intentionally selecting trees that had been damaged from weather or purposefully wounding them during their growth cycle to induce tyloses,” says Thomsen.
“We think of bioengineering as a modern practice, but the samples we have suggest this may have been taking place long before the term was coined in the mid-20th century.”
Bike-sharing schemes
Comparing the locations of the canoe discoveries against maps of ancient trails indicated that the craft were probably not individually owned but shared for the convenience of travellers within communities – as in modern urban bike-sharing schemes. Their availability would have facilitated trading and visits to places of spiritual significance.
Thousands of years ago, the presence of large bluffs would have made travelling over water easier than overland in parts of what is now Wisconsin. Also, net-sinkers found with two of the canoes indicate that they had been used for fishing.
“This project gives us a meaningful opportunity to gain a deeper perspective on our heritage and our ancestors,” says Bill Quackenbush, tribal historic preservation officer for the Ho-Chunk Nation. “The canoes remind us how long our people have lived in this region and how deeply connected we remain to these waters and lands.
“It is important that we document and share these stories so our youth feel that connection to our past. Protecting and preserving this knowledge ensures that the next generation understands where we come from and why these stories matter.”
