Otter Lake got its name from one bad day for the otters

September 29, 1838 was a bad day to be an otter on a certain quiet lake in what’s now Marathon Township. Andrew McArthur, a Columbiaville man who loved to hunt, came through and counted five of them swimming out on the water. He shot one. The name he hung on the place that day — Otter Lake — outlived him, the otters, and the wilderness all three belonged to.

The lake came first; the town arrived later and borrowed the name. The land around it was a tract of pine, thousands of acres of it, eventually bought up by a New York lumberman who wanted the timber. A village platted itself into being in the 1870s, and the post office opened in 1873. The trees that made the place worth coming to were cut, milled, and shipped, the way they were all over the Thumb in those years.

What’s odd is how a single hunter’s offhand label became permanent. McArthur wasn’t founding anything that morning. He was passing through with a gun, saw something worth noting, and the note became a map word — then a depot sign, then a return address. The village still straddles a county line, half in Marathon Township in Lapeer County and half in Forest Township over in Genesee, which means a small town of a few hundred people answers to two county courthouses at once.

Stand on the shore today and the lake is calm, residential, ringed with houses and docks. No otters putting on a show. But the name on every piece of mail leaving town is a receipt for one September morning almost two centuries back, when there were five of them, and then there were four.