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Polluted Runoff: Nonpoint Source Pollution

Darby Duck, the Aquatic Crusader - Critter Scope

Did you ever wonder what life is like under water?

Well now is your chance to find out where different insects and their larvae or nymphs live in a stream. The critter scope is an exploring tool that can peek into the lifestyles of the wet and wiggly world.


  • a can opener
  • a clean coffee can or large juice can
  • waterproof tape or duct tape
  • clear plastic wrap
  • a large and strong rubber band
  • scissors


  1. Carefully remove both ends of the can and cover sharp edges with tape.
  2. Place plastic wrap around one end of the can, leaving about one inch extra around the edge.
  3. Put a rubber band around the can and plastic to keep the plastic wrap tight.
  4. Cut excess plastic wrap away and put tape over the rubber band and plastic wrap.
  5. Take your critter scope for a test run in a sink. Look through the open end and place the closed end (the one with the plastic on it) in the water.
  6. Now you are able to visit the wet and wiggly world of a stream.

Note: You might want to try using a clear plastic cover from a fast food salad as a critter scope too!