Everglades Capstone

Sample Food WebBy LadyofHats (Own work) [CC0], via Wikimedia Commons https://commons.wikimedia.org/wiki/File%3AFood_web_diagram.svg

Consider the food web above depicting a terrestrial food web and a marine food web. In the Everglades, a freshwater marsh, terrestrial and aquatic environments are interconnected. The complexity of this unique ecosystem can be analyzed by constructing a food web to trace the flow of energy between organisms.

Part 1: Your task for this project is to construct an illustrated food web to diagram trophic interactions in the Everglades ecosystem. The food web must be an original creation, you cannot submit a food web that you find online! You must use a minimum of 8 species that are found in the Everglades. You must indicate, using arrows or lines, the flow of energy between the species in your diagram. Be sure to upload your food web as an attachment in the assignment dropbox. Your constructed food web is worth 60 points.

Click here for a resource that will allow you to identify plants and animals that are found in the Everglades.

Part 2: Answer the following questions about the food web you constructed. Answers should be provided on a separate attachment in the assignment dropbox. Answers to the 10 questions using correct spelling and grammar are worth a total of 40 points.

1) List the producer(s) in your food web.

2) List the herbivores in your food web.

3) Are there any organisms in your food web that are omnivores? On which trophic levels are they feeding?

4) List the carnivores in your food web.

5) Identify and list a food chain within your food web that depicts at least three trophic levels. What organism in your selected food chain is a secondary consumer?

6) Are there any nonnative species in your food web? Briefly describe are they altering this food web in the Everglades ecosystem?

7) Choose a primary consumer in your food web. If its population suddenly started to decline, what density-dependent (biotic) factors could be causing it?

8) Choose a secondary consumer in your food web. If its population suddenly started to increase, what density-dependent (biotic) factors could be causing it?

9) Are there any keystone species in your food web? If a keystone species were removed from your food web, how would its loss impact the other organisms?

10) Are there any endangered or threatened species in your food web? If the species goes extinct, how would its loss impact the other organisms?

ANSWER

Everglades Capstone

The figure below shows a food web that consists of organisms that are found in the Everglade’s ecosystem;

The producer in the above food web is the grass. The producers manufacture their food from organic materials through a process called auto tropism (Wang et.al 2020).

The herbivores in the food web are the grasshoppers. The grasshoppers are herbivores because they feed mostly on plants (Wang et.al 2020). In the above food web, the grasshoppers feed on grass which is a plant hence they are the herbivores.

In the above food web, there are no omnivores. Omnivores are organisms that consume a combination of both flesh and plant materials (Welti et.al 2017). In the above food chain, no organism consumes both flesh and plant materials. Omnivores have a positive impact on a food chain because they provide energy in an ecosystem.

The carnivores in the food chain are snakes and cats. These organisms feed on flesh only (Welti et.al 2017).

The food chain that consists of the grass, grasshopper, and the rat contains only three tropic levels. The organism that belongs to the tropic level of secondary consumers is the rat because it depends on the primary consumer -grasshopper- for food (Welti et.al 2017). The nonnative species in the above food web are the eagles. They alter this food web because once they deplete the rats, the snakes and cats will have nothing to feed on.

The primary consumers in the food chain are the grasshoppers, a decrease in grasshoppers could be caused by a decrease in grass that the grasshopper feed on or an increase in the number of rats that feed on the grasshoppers (Wang et.al 2020).

A decrease in the number of rats which are the secondary consumers could be caused by a decrease in the number of grasshoppers or an increase in the number of cats and snakes (Wang et.al 2020). The keystone species in the food web above are the rat. Removal of rats from the food web would lead to a decrease in snakes, cats, eagles, hawks, and vultures.

There are no endangered species in the above food web.

References

Wang, B., Wu, L., Chen, D., Wu, Y., Hu, S., Li, L., & Bai, Y. (2020). Grazing simplifies soil micro‐food webs and decouples their relationships with ecosystem functions in grasslands. Global change biology, 26(2), 960-970.

Welti, N., Striebel, M., Ulseth, A. J., Cross, W. F., DeVilbiss, S., Glibert, P. M., … & Hillebrand, H. (2017). Bridging food webs, ecosystem metabolism, and biogeochemistry using ecological stoichiometry theory. Frontiers in microbiology, 8, 1298.