Food Webs...

Goal: to understand the food chains and webs of distinct ecosystems and the effect of disturbance.

Method: Identify the organisms in your habitat and assign an organism to each group member.

Determine the interactions by creating a food web, as follows:
  1. Ask yourself what your organism must eat in order to survive and identify your "lunch". Give your "lunch" the end of a string in his/her right hand; keep the end with the paper clip in your left hand (this indicates you are eating, not being eaten!)

  2. If your feeding relationship is obligate (i.e. you MUST eat it, such as a herbivore eating a plant no matter what), then, make sure you use a red string.

  3. Repeat as often as necessary until all possible connections are completed.

  4. Now, stand apart so that the strings are taut and you can visualize your food web.

  5. Imagine now, that a disturbance is taking place, say a herbicide, or a disease, you name it! State a hypothesis which describes what would happen to your food web.

  6. Test your hypothesis: dying organisms MUST release their strings and leave the web. What happens to a feeder if the end of a red string in the left hand ends on the floor?

  7. You may wish to redo this using different disturbance models.