Question

data collection: cedar glade population lab
question
how do predator - prey relationships impact population size in the cedar glade ecosystem?
background
in ecosystems of the world today there are many different relationships present between organisms. within those relationships, the organisms involved may be benefited, harmed, or neither. we can classify those relationships based on the impact of the relationship on the organism. one type of relationship that exists between certain organisms is a predator - prey relationship. the effects of predators on prey are important density dependent population controls.
one classic study focuses on the relationship between wolves and moose on isle royale, an island in lake superior. the graph below shows how populations of wolves and moose fluctuated over the time the study was conducted. what drives these population changes?
wolf and moose populations on isle royale
populations of predators and prey may rise and fall over time. sometimes the moose population on isle royale increases enough that moose become easy prey for wolves. when wolves have plenty to eat, their population increases. as the wolf population increases, wolves begin to kill more moose than are born. the predation causes the moose death rate to rise higher than the birthrate, so the moose population decreases. as the moose population decreases, the wolves begin to starve. starvation raises the wolves death rate and lowers their birthrate, so the wolf population also decreases. when only a few predators are left, the moose death rate drops, and the cycle begins again.
in this lab, you will attempt to model the predator - prey relationships found in nature

Explanation:

Predator - prey relationships impact population size through a cyclical process. When prey (like moose) population is high, predators (like wolves) have more food and their population grows. As predators increase, they hunt more prey, causing prey population to decline. With less prey, predators starve and their population decreases, allowing prey population to recover and the cycle repeats.

Answer:

Predator - prey relationships cause cyclical fluctuations in population sizes. When prey population is high, predator population grows due to ample food. Increased predators lead to higher prey mortality, causing prey population to drop. This in turn causes predator population to decline due to starvation, and the cycle repeats as prey population recovers.