Madine Lake is sometimes covered with mist clouds at dawn. They are generated by the temperature difference between the layers of air. This natural phenomenon principally occurs during autumn and spring. In the past, it has happened that pleasure boaters got lost once the coasts disappeared. The fog not lifting, some took refuge on Bois Gérard Island and returned the next day. Some fishermen also reported that they saw coypus circling in the middle of the 2,718 acres lake (1,100 ha), completely lost.