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Polluted Runoff: Nonpoint Source Pollution

Darby Duck, the Aquatic Crusader - No Water off a Duck's Back!

Ducks keep their feathers waterproof by spreading oil from a special gland onto their feathers. However, if excess oil gets into streams, lakes, or oceans, as in an oil tanker spill, it can be harmful to ducks and other water birds.

Oil is one of the most common pollutants in our water. You have probably heard of the Exxon Valdez oil spill. It happened at Prince William Sound in Alaska. Tragedies like this do not happen often, though. Most of the oil in oceans gets there when oil tanks on ships are rinsed while at sea.

When ducks and other waterfowl come in contact with oil floating on top of the water, their feathers become matted. Oily, matted feathers lose their ability to insulate. Because of this, the birds can die from the cold. Also, when the bird tries to clean the oil off of its feathers, it may swallow some of the oil which can lead to stomach ulcers. The only way to save the oil covered birds is to scrub them with detergent, like you might scrub a greasy pan. But this is not a perfect solution. It is very expensive and takes a long time to clean birds.

In this activity you will try several ways to clean up an oil spill. These ways are similar to the ones used by clean-up crews in real life spills. Although oil spills do not happen in all areas, it's good to know how hard it is to clean one up.


  • one large bowl
  • one measuring cup
  • water
  • cooking oil
  • different dishwashing detergents
  • paper towels or a piece of cloth
  • sponges
  • string


  1. Fill half of the bowl with water.
  2. Measure 1/4 cup of oil and pour into the bowl of water.
  3. Gently shake the bowl to create "waves". Did the oil and the water mix?
  4. Now try to clean up the oil using: Paper towel or cloth.
  5. Use string to make a border around the oil and try to drag the oil to one side of the bowl.
  6. Use the sponge to try to soak up the oil.
  7. Try to clean up the oil with each kind of detergent.


  1. List five things you can do, starting today, to reduce the number of pollutants you add to the environment.
  2. Take a field trip to a local stream and see if you can find any type of pollution.