A Hands-On Learning Activity (Study an Oxbow Lake)
Overview
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This learning activity is intended for students in the 6th to 10th grade.
Students will learn about oxbow lakes in the Missouri River basin.
Students and teachers can share what they learn by posting information on the
MRBOIE Facebook page.
The Science of Oxbow Lakes
 First, students need to have an understanding of how oxbow lakes form including
such issues as how river currents affect soil erosion and deposition, how and why
rivers change their course, and the process of succession in which rivers are
transformed over time into lakes, wetlands and other water resources.
o These slides provide a basic overview of oxbow lake science.
o Links at the end of this page will take you to additional resources.
How to Identify an Oxbow Lake
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Identify the location of an oxbow lake by looking at a satellite map
 You can find satellite maps at http://www.maps.google.com
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Zoom in to a location with a river or stream.
This satellite image shows meanders along the Mississippi River.
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When you find that river segment, look for areas where the river meanders or
creates a bend.
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Then find stream segments shaped like a horseshoe or the letter “u” that have
been cut off from the main course of the river. If a stream shaped like a letter “U” is no
longer connected to the river, it may be an oxbow lake.
These “u-shaped” streams in Iowa have been separated from the
main stem of the Missouri River and may be oxbow lakes.
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Look for sites where oxbow lakes once were present that have since
filled with sediment and become swamps, marshes and/or meander
scars.
Meander scars are often found at lower elevations than nearby
landscape features because they once were stream channels.
This satellite image shows meander scars. Meander
scars used to be oxbow streams but have now filled with sediment to become marshes or wetlands.
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Add labels to the map so you can identify precisely where the oxbow is located
and how to get there.
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Road maps help you get to the lake you want to study.
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If you want to visit this oxbow, make sure that you can contact local officials to
see that there is public access and that you won’t be crossing someone’s private
property.
Identify the Topic You want to Study
Once you have chosen the oxbow you want to study, identify if you want to study issues related
to water quality, fauna (animals) or flora at the lake.
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Students exploring water quality may want to
o Use test strips to record levels of pH, nitrates, alkalinity, phosphates.
o Observe sites where water quality changes.
o Record the locations where students saw water quality problems
 Pond scum, water weeds, water that is cloudy, etc.
Students exploring the fauna (animals) might want to
 Observe the animals they see in and around an oxbow lake.
 Record the different types of fish, insects and other aquatic animals
they see in the waters of the lake.
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Record the different types of animals that live near the lake.
 List the type and number of animals each student saw and
where they found them (in the water, on the bank, or on lands
near the lake.
 Use a spoon to dig into a small amount of soil near the lake and later
identify the insects and other animals they found.
Students wanting to examine issues related to flora might want to
o Collect a leaf, stem or flower from each type of vegetation they see at the site,
including plants, flowers, grasses and trees.
o Record where they found different types of vegetation (in the lake or on the
shore) and which plant species were most common.
How You Will Interpret What You Learned.
Students studying water quality issues might want to
 Record the locations where they saw water with different quality,
 Identify land use near the lake that might affect water quality.
 Generate and briefly analyze data from the test strips.
Students studying the animals or fauna might want to
 Make a list of all the animals that were observed, the locations and habitat
types associated with where they were found.
 Mark the locations they found different animals on a map, learn about the
types of animals most-often found at the oxbow lake, and compare your
findings to regional trends.
Students studying vegetation or flora might want to
 Identify the types of plants each student collected.
 Look up photographs of plants commonly found at oxbow lakes in the
region.
 Compare the plants students found with plants most-often found at other
oxbow lakes in the region.
 Identify native and exotic species students found.
 Locate the plant species students found on a map of the oxbow lake.