Habitat Selection

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Purpose

To observe the types of habitats preferred by an organism.

Procedure

1. Obtain a piece of clear tubing (minimum 1-2 inch diameter) that is open at both ends. Obtain stoppers that will effectively seal both ends. Place a line circling the middle of the tube so that you create two halves.
2. Place 10 fairy shrimp (other visible, aquatic invertebrates may be used) in the tubing along with the water they are adapted to.
3. Close and place the tube on its side for 5 minutes. Record the number of shrimp on each side of the tube. Discuss the importance of this as a control measure.
4. Now place a different stimulus (see examples below) on either side of the tube and record the number of shrimp on each side, every minute, for 10 minutes.
   • Hot pack under one side and cold pack under the other.
   • Cotton ball soaked in vinegar on one side, nothing on the other (cotton ball has to go into the tube).
   • Cotton ball soaked in solution of baking soda on one side, nothing on the other.
   • Cover one side with opaque material (dark paper), leave other exposed to light.
   • Place a cotton ball soaked in saturated salt water on one side, nothing on the other.
   • Place some kind of noise (ticking clock, etc.) on one side, nothing on the other.
   • Use your imagination; this can be a more intuitive investigation than a cookbook investigation if treated as such.

Results and Conclusions

After recording data, graph the data and use to predict the types of habitats selected by fairy shrimp.