Oxbow Lake

rivers · nature · water · geology

How they form. Rivers naturally curve and loop back on themselves as they flow downhill. When a loop gets too tight, the river breaks through the narrow part of land between the two bends and rushes straight ahead, leaving the curved part behind as a isolated lake.

Named after oxen. The word oxbow comes from the U-shaped yoke that goes over an ox's neck to help it pull a plow or cart. The curved shape of the loop looks just like that wooden harness.

Always changing shape. Oxbow lakes don't stay the same forever. Over time, they slowly fill with sediment and plants until they become shallow wetlands or disappear entirely. Some eventually turn back into part of the river's floodplain.

Wildlife paradise. These quiet, cut-off lakes become amazing homes for fish, turtles, frogs, and water birds because the still water is perfect for life to thrive away from the river's fast current.

Recent and common. New oxbow lakes are still forming today wherever rivers curve and wind through flat land, making them one of the earth's most dynamic natural features.