Rediscovering Lake Aagonweton, a treasure that maps forgot

My neighbor, Ruth King, is an avid dogsledder. Over the years she has occasionally extended an invitation to join her for a romp through the snow. The day we picked, and our destination ended up being one of the most extraordinary adventures of my life.

The cold bit as I helped Ruth snap the dogs onto the gangline. Of all the days to pick for this excursion it figures that it would land during this winter’s one cold snap. It was the kind of weather that makes you glad for the Covid mask. The thermometer read 28 below when I left my house before dawn that morning but I think was colder where we set off – wherever that was – and the dogs were anxious to get going. In the winter the place we were going to is only accessible by dogsled – or snowshoe, if you’re willing to take the time and risk the trek over the sketchy terrain.

What terrain it is I cannot tell you, other than that it is in Washburn county, WI and it is somewhere near Lake Aagonweton, our ultimate destination. If you have not heard of Lake Aagonweton you are not alone. It is not on any map, and until recently only a handful of people in the world knew of its existence. My guide, Ruth insisted that I wear a black sack over my head as we drove with the dogs and sled to this remote location, hidden off of one of Washburn county’s labyrinthine logging roads. The secrecy is understandable. Lake Aagonweton is one of only two salt lakes between the Atlantic Ocean and The Great Salt Lake, in Utah. The other, Salt Lake, near Marietta, Minnesota, is only twenty acres. A dwarf compared to Aagonweton’s 457 acres.

Once the dogs were hooked up Ruth and I began our journey over the marshes that surround Lake Aagonweton. Ruth had been out here twice earlier that week, but even with the broken trail it took us two hours to wend our way to the frozen lake waters. In that time the marshes around us underwent an incredible transition from freshwater to saltwater marsh habitat. It was the first hint of the incredible ecological treasure that the county has come to own thanks to a generous gift from a donor who has chosen to remain anonymous. The lake and surrounding acreage has been held privately, and very secretly, by the donors’ family for the last 150 years.

The first European to encounter Lake Aagonweton was Father Jean Saispas, one of the members of Etiennes Brule’s exploration party. The lake can be found on Brule’s 1632 map of the area, but for reasons that are still obscure the lake disappeared from all subsequent maps. It was only after a small county subcommittee – made up of Ruth and three other members – explored the newly gifted land last spring that anyone outside of the previous owner’s family even knew of it. But even the previous owners had not realized what a unique and rare locale Lake Aagonweton represented.

In the short time since the donation last summer, Ruth’s committee has identified 73 rare and previously unknown species which have adapted to the extraordinary habitat Lake Aagonweton provides. Among them are:

• Taylor’s Salamander, a species of saltwater salamander previously found only in a high altitude crater in Laguna Alchichica, Mexico
• The first known species of saltwater frog (Rana Nugae) found in North America
• A new species of wild rice that has adapted to saltwater.
• An amazing miniature relative of the Shortbill Marlin with a sword about five inches long.

In addition, the lake is a premier stopover site for migrating birds. Because of its salt content Lake Aagonweton is one of the first lakes to open in the spring and in a few scant weeks there will be pelicans and albatrosses catching a rest on their way to Hudson Bay. Blue and Saltmarsh Herons will be fishing the rich waters near the marsh. Sandpipers and egrets will watch over terrapins basking on logs.

It will take years to do a thorough autecological assessment, surveying all of the species and how they interact with the surrounding habitat. This is why Ruth and her committee are keeping the location so under wraps. “Not even the full county board knows about this place,” she told me. “We want to know exactly what we have here before we start making decisions about what to do with it.”

Certainly, with all it has to offer, Lake Aagonweton could be a destination tourist site – a possibility that could boost economic development but has enormous implications for the fragile ecosystem. A greener alternative might be using the salt marshes for carbon sequestration credits – a possibility the county is already looking into. In any case, standing on the edge of this primal and heretofore unknown lake, I feel a sense of awe at being a North Wisconsin resident. A land so rich with surprising gifts.