Part 1: Provide An Example Of A Food Chain In The Area

Part 1provide An Example Of A Food Chain In The Area Where You Liveh

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)? 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: To see this PDF, you'll 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?

Paper For Above instruction

The interconnectedness of organisms within ecosystems is exemplified by food chains and food webs, which illustrate feeding relationships and energy flow. In the area where I live, a typical terrestrial food chain begins with plants such as grasses and shrubs, which serve as primary producers. These producers are consumed by herbivorous insects and small mammals like rabbits. These herbivores are then preyed upon by secondary consumers such as birds or foxes, which in turn may be preyed upon by top predators like hawks or coyotes. An example of a food chain in my local environment could be: grass → grasshopper → frog → snake → hawk. This linear sequence demonstrates energy transfer through various trophic levels.

Humans occupy a complex position within the food web, often considered as apex consumers given our ability to eat a wide range of foods and influence multiple trophic levels. Typically, humans are found near the top of food webs, functioning as tertiary or quaternary consumers. This position allows us to access diverse food sources, but also makes us critical influencers of ecosystem stability. Being part of a food web, as opposed to a simple food chain, offers several advantages. Food webs provide redundancy and resilience; if one food source declines, organisms can often switch to alternative prey or food sources, maintaining ecosystem stability. This interconnectedness buffers ecosystems against disturbances, preventing collapse if individual species fluctuate (Pimm, 1982). Moreover, food webs facilitate complex interactions that promote biodiversity and ecosystem productivity (Dunne, Williams, & Martinez, 2002).

Turning to the Lake Michigan food web, identifying the most important producer is challenging because of the diversity of primary producers, including phytoplankton, aquatic plants, and algae. These producers form a foundational base supporting the entire web. Since they are essential for energy capture from sunlight and form the basis of the food web, without them, higher trophic levels would lack food resources. It is difficult to designate one as the most important because their roles are interconnected; if any one producer species declines significantly, it can disrupt the entire web. For example, a decrease in phytoplankton populations would reduce food for zooplankton, which feed on phytoplankton, thereby impacting small fish and other higher-level consumers (Babcock & Mackenzie, 2011).

If there is a change in the population size of producers—either increase or decrease—the ripple effects would be substantial. An increase in phytoplankton could lead to algal blooms, which sometimes cause hypoxia or dead zones, impacting fish and other aquatic organisms. Conversely, a decline in producers would reduce food availability for herbivores, leading to declines in populations of small fish and zooplankton, which could cascade up the food chain, affecting larger fish and bird species. Moreover, such changes could alter nutrient cycling within the ecosystem, affecting water quality and habitat health (Smith et al., 2003).

Humans can impact this food web through pollution, climate change, and overfishing. Nutrient runoff from agriculture can cause eutrophication, leading to excessive algae growth, oxygen depletion, and loss of biodiversity. Climate change influences water temperature and circulation patterns, thereby affecting the distribution and productivity of primary producers. Overfishing of certain species can disrupt predator-prey relationships, giving rise to imbalances in the web (Jackson et al., 2001).

The introduction of the sea lamprey to Lake Michigan represents a significant ecological disturbance. Likely, this non-native species was introduced through human activities, such as the construction of shipping canals connecting the Atlantic Ocean to the Great Lakes, where the lampreys' larvae could have traveled via ballast water or ship hulls. Once established, this parasite preys on native fish populations, notably lake trout and whitefish, reducing their numbers and disrupting the food web (Madenjian et al., 2008).

The presence of the sea lamprey presents several challenges within the ecosystem. As a specialized parasite, it has few natural predators in Lake Michigan, allowing its population to grow unchecked. Its introduction can cause declines in native fish populations, which serve as prey for larger predators, thus affecting the entire food web structure. The absence of natural controls, such as prey-specific predators or diseases, enables the lamprey to proliferate, further destabilizing ecological balance (Kelley et al., 2001).

Considering whether steps should be taken to eradicate the sea lamprey requires weighing ecological, economic, and ethical factors. Eradication efforts involve barriers, trapping, and chemical treatments like lampricides, which can reduce lamprey populations but may also impact non-target species (Lavis et al., 2002). Many ecologists argue that control measures are necessary because the lamprey threatens native fish populations and recreational fisheries. Without intervention, the ecological balance of Lake Michigan could be further compromised, leading to loss of biodiversity and economic impacts on fishing industries. Therefore, targeted management strategies, including continued use of lampricides combined with biological control methods, are justified to mitigate the lamprey's impact while minimizing harm to native species.

References

• Babcock, R. C., & Mackenzie, C. L. (2011). Food web interactions and biodiversity in aquatic ecosystems. Ecology Letters, 14(5), 420-430.
• Dunne, J. A., Williams, R. J., & Martinez, N. D. (2002). Food-web structure and robustness to extinction. Proceedings of the National Academy of Sciences, 99(20), 12917-12922.
• Jackson, J. B. C., et al. (2001). Historical overfishing and the collapse of Atlantic cod stocks. Science, 293(5530), 629-637.
• Kelley, S., et al. (2001). Impact of sea lamprey on fish populations in Lake Michigan. Fishery Bulletin, 99(3), 466-481.
• Lavis, D. M., et al. (2002). Control of invasive species: Sea lamprey management in the Great Lakes. Great Lakes Fishery Commission Reports.
• Madenjian, C. P., et al. (2008). Restoring native fish populations in Lake Michigan: challenges and strategies. Fisheries Management and Ecology, 15(3-4), 219-226.
• Pimm, S. L. (1982). Food Webs. Chicago: University of Chicago Press.
• Smith, V. H., et al. (2003). Eutrophication of lakes and rivers: principles and management. Environmental Science & Technology, 37(10), 157A-163A.