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Image Collage of Bay of Fundy
Bay of Fundy Title
Bay of Fundy Image
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Tidal fall in the
Bay of Fundy
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Welcome to the world's largest bathtub! That's the image to keep in mind when thinking about the Bay of Fundy. In no section of the Gulf are the tides more dramatic than here in the Bay, where the water may rise and fall as much as 50 feet (16m) each day.

Image of Rocky headlands, Cape Hopewell
Weathered headlands, Cape Hopewell.

The Bay of Fundy is a 170-mile-long (270km), straight-sided, somewhat funnel-shaped bay which splits at its northeastern head into two narrow bays, Chignecto Bay and the Minas Basin. It was formed as the continental plates parted millions of years ago. As they split, deep rift valleys formed, which quickly filled with sediment washed in from the land. The Bay of Fundy is one of these ancient rifts.

image of boat on mudflats at low tide

The great tides of the Bay of Fundy are due to two unique characteristics of this finger of the Gulf. The bay itself is U-shaped, and tapers significantly at its northernmost end. Naturally, as the tide flows into the Gulf of Maine and enters the Bay of Fundy, it rises up in response to this constriction. Furthermore, the time it takes for the tide to move up the Bay of Fundy is nearly identical to the time it takes for the tide to come in from the open Atlantic. This means that the tides range is amplified, similar to the effect produced by children sloshing water into waves in a bathtub. These two factors, combined with several other lunar features, make the tides of the Bay of Fundy a natural wonder of the world.

scientist in submarine

Visitors to the region speak in wonder of the "tidal bore," a small but fast-moving wave of water that is the face of the tide. Each day as the tide comes in, the tidal bore races across the the mud flats and up the Bay's coves and rivers, in turn bearing a rich load of nutrients back into the Gulf as it ebbs.

image of tidal bore below Saint John bridge
Outgoing tidal bore in Saint John, New Brunswick.

The upper region of the Bay of Fundy features extensive mud flats and expansive salt marshes. These occur as a result of the tides. During each tidal cycle, huge quantities of fine sediments are brought in to flood the coastal area. Much of the sediment remains in the sheltered areas along the coast, forming the famous red mudflats of the upper Bay. The mud flats and salt marshes are vital pieces of the Bays food production system.

image of four lobster boats on mud in Alna, New Brunswick
Lobster boats high and dry at low tide, Alma, New Brunswick.

Because the tides churn the water up each day, the water is rather turbid, or cloudy. The rays of the sun cannot reach very deeply into the water column, thus phytoplankton cannot photosynthesize. However, when the tide ebbs, it leaves behind a wealth of nutrients on the mud flats fully exposed to the sun. As a result, phytoplankton production is very low in the water but extremely high on the mudflats and salt marshes. In addition, both intertidal areas contribute vital nutrients to the Bay of Fundy ecosystem.

image of muddy water against rocky shoreline
Turbid waters where the shore meets the bay.

The mudflats also provide a larder of food to hungry migratory shorebirds. Each year up to two million semi-palmated sandpipers and other shorebirds stop over in the Fundy region during July and August on their annual migration from their spring breeding grounds, far to the north on the arctic tundra near Hudson Bay, to their wintering grounds along the coasts of South America. The semi-palmated sandpipers that settle in the Minas Basin and other areas represent 75-95% of the entire world's population of this species. They build up their body fat on tiny crustaceans found only in mud of a certain consistency.

scientist in submarine
Hermit crab feeding on mussel beds.
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Due to the strength of the tide, the Bay acts as a vast nutrient pump for the rest of the Gulf of Maine, sending its waters whirling out past Grand Manan Island to mix in the Gulf of Maine current. It is around Grand Manan Island that one can see the great whales cavort in the early fall each year.

Drawn by the rich waters flowing from the Bay of Fundy and the resulting abundance of phytoplankton and fish in the area, the whales — such as humpback, minke, sei, and the rare right whale — come to feed and court. Recognizing the vital role the waters around Grand Manan Island play in the life cycle of the endangered right whale, the Canadian government established a seasonal Conservation Area from June to October each year. The areas around Grand Manan and nearby Roseway Basin are the only known locations where right whales can be observed in the summer and fall, according to reports.

image of a whale surfacing
Fin Whale feeding on a tidal upwelling of phytoplankton
on the north side of Grand Manan.

Just south of Grand Manan Island is Machias Seal Island, a speck of rock on which a resurgent population of puffins lives. Their presence is testament to the relatively undisturbed character of this corner of the Gulf of Maine.

image of bay of Grand Manan island
Looking out from Grand Manan Island to the Bay of Fundy.
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Bay of Fundy map
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Bay of Fundy in 3D
Click on the map above to explore the journey area.
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Related information: 
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Click here to see a movie
of tidal fall and rise
in the Bay of Fundy

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Special Thanks: 
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Edward French,
The Quoddy Tides, Eastport, Maine
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Images and Video ©Bill Curtsinger,
All Rights Reserved
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