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1. What is the second largest rodent in the world?

2. What features of a stream make it a suitable location for beavers to build a dam?

3. How long can beavers hold their breath under water?

4. Why are beaver dams often concave in shape?

5. How long do the male and female beavers stay as a pair?

6. How long do beaver kits stay with their parents before dispersing to find their own territories?

7. What do beavers build to live in?

8. How does the presence of beaver dams help people the most?

9. Beavers change their environment to benefit their own success through a process called “ecosystem engineering”. What are some of the physical outcomes of their engineering activities, and how might these outcomes aid the success of other species and ecological processes as well?

10. During the global fur trade of the 16th to 19th century, both species were almost hunted and trapped to extinction both in Eurasia (for the Eurasian beaver) and North America (for the North American beaver). Both species have since made dramatic recoveries throughout much of their former ranges. How might the extinction of beavers throughout the northern hemisphere have altered biodiversity and ecological processes?

11. The term “ecosystem engineer” refers to a species that alters the physical aspects/structure of its environment. Many scientists also consider beavers to be a “keystone species”, which is a species that has a disproportionate effect on the entire ecosystem, particularly through food webs. If a keystone species is removed from a system, the whole system would likely collapse. How would the reintroduction of beavers into their previously occupied habitats influence other organisms in the food web? Which type of species might benefit the most?