Understanding the Impact of Dams on Ecosystems

What is the primary purpose of the salmon cannon?

• To measure water flow

• To shoot fish upriver

• To transport salmon downstream

• To clean the river

What percentage of the world's electricity is generated by hydroelectric energy?

• 25%

• 50%

• 16%

• 10%

Which of the following is NOT a consequence of disrupting river flow with dams?

• Blocked sediment flow

• Toxic water accumulation

• Improved fish migration

• Increased water temperature

What is one of the main reasons salmon populations have been declining?

• Overfishing

• Pollution

• Dam installations

• Climate change

Which of the following is NOT a method used to help fish navigate past dams?

• Fish ladders

• Fish elevators

• Fish nets

• Fish cannons

What is a significant benefit of removing a dam?

• Increased water storage

• Improved recreational activities

• Restoration of natural river flow

• Higher electricity production

Which river is highlighted as a successful example of dam removal?

• Columbia River

• Amazon River

• Mississippi River

• Elwha River

What role do beavers play in the ecosystem after dam removal?

• They decrease fish populations

• They increase water pollution

• They transport seeds and alter plant communities

• They build new dams

Why is it unrealistic to remove all dams?

• They provide essential resources like water and energy

• They are historical landmarks

• They are too expensive to remove

• They are protected by law

What is a realistic approach to managing existing dams?

• Ignoring their environmental impact

• Making them more environmentally friendly

• Building more dams

• Removing all dams