Summary: Migration is a crucial, yet demanding component of the life history of many animals, often spanning thousands of kilometers and posing significant challenges to survival. Studying migration can be particularly challenging for cryptic and nocturnal species. Bats, one of the most diverse mammalian taxa, display migratory behaviours that vary from short regional movements to long continental migrations. In Canada, three bat species undertake long-distance latitudinal migrations, all of which are listed as endangered due to the increased mortality during migration caused by wind turbines. Our research focuses on the habitat requirements of one of these species, the Silver-haired Bat, during migratory stopovers. While out in the field working on this project, we got word of a remarkable observation made by two citizen scientists. They observed a large diurnal migration of Silver-Haired Bats over Lake Michigan. Over 400 bats were seen flying towards shore, with more than 100 observed roosting at a nearby park in Chicago. While systematic studies allow us to test hypotheses about the natural world, it is often these rare observations that highlight how much we have yet to understand about natural phenomena such as migration. .