Energy and Food Webs

Part 1:

Provide an example of a food chain in the area where you live.

Humans are parts of food chains and food webs, too. Where on a food web would you typically find humans (near the bottom with the producers, at the top with carnivores, or somewhere in between)? Explain.

What are some advantages of being part of a food web rather than a food chain?

Part 2:

Here is a food web for Lake Michigan:

http://www.glerl.noaa.gov/pubs/brochures/foodweb/LMfoodweb.pdf

To see this PDF, you will need to download the free Adobe Reader.

In the Lake Michigan food web, is it possible to identify the most important producer? Why or why not?

What would happen if there was a change in the population size for any one of the producers (either an increase or a decrease)? How could these changes impact other producers and organisms on other trophic levels?

Provide at least two types of impacts that humans could have on this food web.

Read the description of the sea lamprey on page 2 of the food web. This species is described as non-native.

Propose a mechanism for how this fish was introduced to Lake Michigan.

What challenges could occur within a food web when a new predator like this is introduced into an ecosystem?

What natural population controls are missing for this species within this food web?

Do you think steps should be taken to eradicate this species from the food web? Explain why or why not? If so, what steps can be implemented?