SIERRA NEVADA FOOD WEB ACTIVITY
1. With your team, take a large piece of butcher paper and then write down the
name of each of the organisms (from the back side of this sheet) randomly all over
1a. Identify the role of each organism by putting one of the following letters just
beneath the name of the organism:
P (producer), C (consumer), D (decomposer or detritus feeder), and S (scavenger).
Then circle each organism along with its letter.
2. Now draw a line from any food to the organism that eats it. These lines represent
the direction in which energy flows in an ecosystem and should always have arrow
tips that point from the food towards the organism that is eating the food.
3. Once the team has completed that chart, it is time for each individual team
member to do an assignment. Find and write out on a separate piece of paper, eight
different food chains from your team food web.
4. On two of your food chains, identify the producer and three levels of consumers.
5. From the food web identify three organisms that are at the top of their food
6. If the secondary consumers in one of the food chains use 4,200 kcal, what amount
of energy was absorbed by the producers in that food chain? What amount of
energy will be available to the tertiary consumers?
7. Please describe what the differences between a pyramid of energy, a pyramid of
numbers, and a pyramid of biomass are.
8. Please describe what would happen to this food web if all the primary consumers
9. Please describe what would happen to this food web if the decomposers were
10. What would happen to this food web if a non-native beetle started killing all the
11. What do you think is more resilient, food webs with many species, or food webs
with just a few species? Please explain your answer fully.
ORGANISMS FOUND IN THE SIERRA NEVADA ECOSYSTEM
California Bat (flying insects)
Mountain Lion (deer, rabbits, large rodents, and bighorn sheep)
Black Beer (berries, insect larvae, small mammals, nuts, tubers)
Bob Cat (small mammals and birds)
Oak Moth Larva (oak tree leaves)
Mosquitoes (protests and mammal blood)
Coyote (scavenger, rodents, rabbits, vegetable matter)
Lodgepole Chipmunk (acorns, seeds)
California Ground Squirrel (acorns, seeds, mushrooms, birds, insects)
Yellow-bellied Marmot (grasses)
Mule deer (grasses and herbaceous plants)
Stellar Jay Bird (insects, worms, larvae)
Great Horned Owl (rodents, lizard, snakes)
Beetles (plants, fungus)
California King Snake (rodents)
Bracket fungus (decomposer)
Raccoon (fruits, nuts, insects, frogs)
Golden trout (mosquitoes, insect larvae)
Bighorn sheep (grasses, herbaceous plants)
Mayfly larvae (aquatic plants)
Acorn woodpecker (acorn, insects)
Worms (dead plants and animals)