When Wolves Were Returned to Yellowstone National Park in 1995

question 12

Essay

When wolves were returned to Yellowstone National Park in 1995, they immediately began feeding on elk, reducing their numbers. This allowed aspen trees to increase in abundance, which ushered in the return of beaver populations. As beaver populations dammed streams, they slowed water flow and stabilized streambanks. The stabilization of streambanks increased riparian habitat in which songbirds could nest, and the ponds provided breeding habitat for amphibians. Explain this story using the concepts of top-down and bottom-up control.

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Definitions:

Proved Reserves

Specific mineral deposits that have been shown by scientific examination and cost calculation to be extractable and deliverable to the market for use, with current technology and expected market conditions.

Mineral

A naturally occurring, inorganic solid with a definite chemical composition and crystalline structure, used in various industries.

Conservation

The sustainable management and use of natural resources to prevent depletion or degradation, safeguarding biodiversity and ecosystems.

Scarcer

Describes a condition where resources, goods, or services become less available or in shorter supply than previously.