Conservation Biology Laboratory 8

Whitebark Pine Communities: Community Ecology

The book, Whitebark Pine Communities: Ecology and Restoration, provides us with some state of the art management studies (as well as a nice demonstration of ecological concepts) on, perhaps, one of the hottest issues facing managers in the northern Rocky Mountains today. The potential loss of an important keystone species, Pinus albicaulis, across wide areas of alpine habitat could have significant ecological ramifactions. The whole structure of the alpine community could be effected by damage to whitebark pine populations. You will see that whitebark pine trees are threatened as a result of a variety of issues (beetle infestation, exotic disease introduction, fire suppression and, perhaps, management policies themselves).

Please read Chapters 5, 6 and 7 in Whitebark Pine Communities: Ecology and Restoration.

Please answer the following questions on Chapters 5, 6 and 7 (there are 10 questions):

Laboratory 8

1. What role does Clark's Nutcracker play in the ecology of the Whitebark Pine?

2. What kind of sites are used for seed caches by Clark's Nutcracker? How many seeds to

they store per cache?

3. How many seeds are estimated to be cached/needed by the average nutcracker per year?

4. Why are whitebark pine trees often found as "clumps of trunks"?

5. What are the 3 phases of whitebark pine natural regeneration?

6. At what age can whitebark pine trees start producing cones?

7. List some factors that reduce the potential for natural regeneration of whitebark pine trees?

8. Why are whitebark pine seeds important to bears?

9. What role do the middens collected by red squirrels play in the food web?

10. Why are grizzly bears vulnerable to the loss of whitebark pine trees in the Greater Yellowstone Ecosystem? What are the potential threats to the trees in the GYE?