Ecology of Yellowstone National Park

What ecological role do bison play in Yellowstone’s grassland ecosystem?

• Apex predators

• Primary consumers

• Decomposers

• Secondary consumers

Which trophic level do gray wolves primarily occupy in Yellowstone’s food web?

• Primary producers

• Primary consumers

• Secondary consumers

• Tertiary consumers

How does the reintroduction of wolves in 1995 impact the riparian vegetation in Yellowstone?

• Decreases vegetation due to overgrazing by elk

• Increases vegetation by reducing elk populations and their browsing

• Has no significant impact

• Reduces vegetation due to increased predation on beavers

What adaptation helps the pika survive the harsh winters in Yellowstone?

• Thick fur and burrowing

• Migration to lower altitudes

• Hibernation

• Storing food in haypiles

Which of the following is a keystone species in Yellowstone National Park?

• Bison

• Cutthroat trout

• Grizzly bear

• Gray wolf

What is the primary reason for the decline in cutthroat trout populations in Yellowstone?

• Overfishing

• Introduction of non-native lake trout

• Climate change

• Pollution

How do beavers contribute to wetland ecosystems in Yellowstone?

• By increasing fish populations

• By preventing forest fires

• By creating ponds and wetlands through dam-building

• By spreading seeds of aquatic plants

What is the main diet of the Yellowstone grizzly bear in the fall?

• Freshwater fish

• Insects and small mammals

• Nuts, berries, and whitebark pine seeds

• Large ungulates like elk

How do thermophilic bacteria in Yellowstone’s hot springs contribute to the ecosystem?

• By producing oxygen through photosynthesis

• By breaking down organic matter

• By providing a food source for other microorganisms

• By fixing nitrogen from the atmosphere

Which factor is most likely to influence the migration patterns of elk in Yellowstone?

• Availability of freshwater sources

• Seasonal changes in vegetation

• Presence of predators

• Human activity in the park