The River That Divides the Water

The Niagara River connects two Great Lakes — but the Falls split its ecosystem in half.

The drop is too powerful for fish to cross. Over thousands of years, the river above the Falls and the river below have developed largely separate fish communities — like two neighbourhoods divided by a wall. Above the Falls, Lake Erie's warmer water supports fish like walleye and smallmouth bass. Below, the colder lower river connects to Lake Ontario, home to its own communities. Some species live on both sides, but the Falls keep the two groups apart.

Birds don't have that problem. The Niagara River is one of the most important bird flyways in eastern North America. Bald eagles, ospreys, peregrine falcons, and huge numbers of ducks, geese and gulls pass through every spring and fall. In winter, when much of the region freezes over, parts of the river stay open, and the gathered birds draw birdwatchers from across the continent.

The Falls divide the fish. They gather the birds. All from one dramatic drop in the river.