08/18/2026
Most people understand tides as a daily inconvenience, a few hours of difference in beach access, a bit more mud exposed at the marina at low tide, nothing dramatic. The Bay of Fundy is an education in what tides actually are. The bay runs between New Brunswick and Nova Scotia, narrowing as it extends northeast into two sub-basins, Minas Basin and Chignecto Bay. The physics of what happens in that funnel shape is called resonance, and the Bay of Fundy is one of the most extreme examples of tidal resonance on the planet. The natural period of water sloshing back and forth in the bay, about 13 hours, happens to closely match the 12.4-hour period of the dominant tidal forcing from the moon and sun. The result is an amplification of the tide that becomes more extreme as you move into the narrower reaches of the bay. At the mouth, tidal ranges are already larger than most places in the world. At Minas Basin, the innermost part of the bay near Wolfville Nova Scotia and Parrsboro, the tidal range regularly exceeds 16 metres and occasionally reaches 17. For context: 16 metres is taller than a five-story building. Boats that are floating normally at high tide are sitting on exposed red mud 16 metres lower six hours later. The amount of water moving in and out of the bay in each tidal cycle is approximately 160 billion tonnes, an often-cited figure that is impossible to visualise meaningfully except to note that it is more than the combined discharge of all the freshwater rivers on Earth in the same period. The Fundy tidal ecosystem supports an extraordinary concentration of migratory shorebirds, who come to feed on the rich invertebrate life in the exposed mudflats.
