Food Chain and Food Web Activity

Directions
Food Chain and Food Web Activity
1. With colored pencils color the boxes like this:
Energy source – Yellow
Producers – Green
Herbivore (Primary consumer) – Blue
1 st order carnivores (Secondary consumers) – Orange
2 nd order carnivores (Tertiary consumers) – Red
Scavengers – Purple
Decomposers – Brown
2. On the back of this page, construct 2 food chains by writing the name of the organism in the in
the spaces provided. Color-code each box using the colors given above.
3. Use the pictures to form a food web by first arranging them on your desk. Remember that a food
web is several food chains linked together. Use the information provided in the boxes to make
sure that your web is correct. Glue or tape your food web onto a sheet of paper. Use arrows to
show that energy is passed from one organism to another. Arrows go from the animal that is
eaten to the animal doing the eating.
4. Your teacher will tell you the name of a “poisoned organism”. Put a star by this organism’s name
to indicate that they have been sprayed with an insecticide (bug spray), or have eaten an
organism that has been sprayed with one of these compounds. If animals also eat the organism
that has been sprayed, they take in the poison. The animals may not die, but the poison builds up
in the organs of its body. Because larger animals eat more food that may be affected with the
poison, more poison is naturally concentrated in the larger animals.
5. Take a dark colored pencil and put a star by all of the organisms in the food web that might get
some of the poison in their bodies from their food.
6. When you have done 1-5, answer the following questions on the back of your food web. Use
complete sentences.
a. What would happen if there were more predators than prey in an ecosystem? Explain.
b. Why are the 2 nd level carnivores more likely to be affected by the insecticide than 1 st level
carnivores?
c. Explain what may happen to the other organisms if disease were to kill off one of the 2 nd level
carnivores in your food web. Which organisms would increase in population? Why? Which
organisms would decrease in population? Why?
d. Describe how humans might change (or are currently changing) the food web.
e. Why can’t food chains go on forever? (8 th order, 9 th order, and 10 th order consumers?)
Answer in terms of energy (think of an energy pyramid)

Energy Source
Name
Hour
Producer Producer
Primary Consumer Primary Consumer
Secondary Consumer Secondary Consumer
Tertiary Consumer Tertiary Consumer