Chapter 7: Forests and Wildlife Big Question Can We Have Them and Use Them Too?

Lesson 7 / ESRM 100 / University of Washington Forestry: Keeping Our Living Resources Alive For both forests and commercially valuable wildlife, the traditional goal has been the maximum sustainable yield. This goal is based on traditional concepts: belief in the balance of nature.

Lesson 7 / ESRM 100 / University of Washington Modern Conflicts over Forestland and Forest Resources What’s “natural” and what isn’t? Growing trees has become a profession called silviculture. Civilizations have literally been built on wood. Forests also have had religious, spiritual, and aesthetic importance.

Lesson 7 / ESRM 100 / University of Washington Clearcutting

Lesson 7 / ESRM 100 / University of Washington Muir and Pinchot At the heart of the conflict are the two different kinds of values, utilitarian and nonutilitarian. John Muir (with Theodore Roosevelt at his left, in the left-hand photo) and Gifford Pinchot (right) personify the two viewpoints.

Lesson 7 / ESRM 100 / University of Washington Hetch Hetchy The dam at Hetch Hetchy led to one of the greatest arguments between Muir and Pinchot.

Lesson 7 / ESRM 100 / University of Washington Controversial Questions Should a forest be used only as a resource to provide materials for people and civilization? Should a forest be used only to conserve natural ecosystems and biological diversity? Can a forest be managed for timber harvest and also meet recreation, landscape beauty, and spiritual needs? Can we achieve sustainable forests? What role do forests play in our global environment? What is “natural” in a forest? How much old growth do forests need?

Lesson 7 / ESRM 100 / University of Washington International Aspects of Forestry

Lesson 7 / ESRM 100 / University of Washington Plantation Forestry

Lesson 7 / ESRM 100 / University of Washington Are the World’s Forests Shrinking, Growing, or Neither? We lack enough information to accurately evaluate the situation, but this situation has begun to change with remote sensing and geographic information systems.

Lesson 7 / ESRM 100 / University of Washington Indirect Deforestation A more subtle cause of the loss of forests is indirect deforestation--the death of trees from pollution or disease. Why trees are dying appears to involve a number of factors. Acid rain, ozone, and other air pollutants weaken trees and make them more susceptible to disease. Global warming could cause widespread damage.

Lesson 7 / ESRM 100 / University of Washington Wildlife Management Traditional Wildlife Management Modern conflicts about wildlife are similar to those about forests. How has wildlife been faring? Many species of wildlife have declined greatly in abundance, some have become endangered, and some have gone extinct.

Lesson 7 / ESRM 100 / University of Washington Bison on the Range and Then Mostly off the Range How many bison were there to begin with? Perhaps 50 million?

Lesson 7 / ESRM 100 / University of Washington Test Case: Pribilof Island Reindeer The islands seemed perfect for introduced reindeer: lots of plants and no predators.

Lesson 7 / ESRM 100 / University of Washington Decline of the Pribilof Island Reindeer Even so, something went very wrong with the Pribilof Islands reindeer. Population initially increased, then declined severely.

Lesson 7 / ESRM 100 / University of Washington Improved Approaches to Wildlife Management Four principles of wildlife conservation: a safety factor in terms of population size; concern for the entire community of organisms and all the renewable resources; maintenance of the ecosystem of which the wildlife are a part; and continual monitoring, analysis, and assessment.

Lesson 7 / ESRM 100 / University of Washington Time Series and Historical Range of Variation How do we decide what is a sustainable population if the natural population is always changing? One answer is to consider a range of population levels natural. A time series of population estimates provide the historical range of variation. Such records exist for only a few species.

Lesson 7 / ESRM 100 / University of Washington Example: American Whooping Crane In the late 1930s, the population was 14. The number born that year was also counted. We can use this historical range to estimate the probability of extinction.

Lesson 7 / ESRM 100 / University of Washington The American Whooping Crane's Recovery Prediction of extinction was very low: less than one in a billion. As predicted, whooping cranes have continued to increase. Breeding programs have further boosted the number of whooping cranes.

Lesson 7 / ESRM 100 / University of Washington Managing Two or More Species at a Time: Do Predators Matter? It appears that predators probably play a smaller role than we thought—for example, Hudson’s Bay Company trapping records suggest Canadian lynx do not neatly control the abundance of Arctic hares.

Lesson 7 / ESRM 100 / University of Washington Large Influence of Some Predators Predators can have large effects in some cases. For example, m0squito fish can greatly reduce mosquito abundance. An absence of predators can have a major effect, too. Introduced Asian water buffalo in Australia increased too rapidly, causing large die-offs. In this case, not just the water buffalo but also their habitat suffered.

Lesson 7: Forests and Wildlife Questions? your TA.