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Text 1
In parts of the Northwest Territories, Canada, the rough-legged hawk is a major predator of the collared lemming. Researcher Alice Kenney and colleagues found that when this predation pressure on collared lemmings was temporarily reduced, their numbers significantly increased. This finding illustrates a foundational ecological principle: predators control prey population numbers.
Text 2
Robert D. Hayes and colleagues found that excluding wolves from a site in Yukon, Canada, where they typically prey on Dall sheep had no significant effect on Dall sheep abundance. Many other predation relief studies show an increase in prey abundance, but those studies often focus on small, rapidly reproducing prey, like birds, lemmings, and rabbits, rather than large, slowly reproducing prey, like Dall sheep, which could account for the difference between those results and Hayes and colleagues' results.
In parts of the Northwest Territories, Canada, the rough-legged hawk is a major predator of the collared lemming. Researcher Alice Kenney and colleagues found that when this predation pressure on collared lemmings was temporarily reduced, their numbers significantly increased. This finding illustrates a foundational ecological principle: predators control prey population numbers.
Text 2
Robert D. Hayes and colleagues found that excluding wolves from a site in Yukon, Canada, where they typically prey on Dall sheep had no significant effect on Dall sheep abundance. Many other predation relief studies show an increase in prey abundance, but those studies often focus on small, rapidly reproducing prey, like birds, lemmings, and rabbits, rather than large, slowly reproducing prey, like Dall sheep, which could account for the difference between those results and Hayes and colleagues' results.