A unit of Lasting Forests Sustained forests; sustained profits evolving since March 30, 1999

Wildlife management is a part of natural resource management or wildland management. No terms are adequate; their meanings have been blurred by years of misuse. Why plants, aquatic life, and terrestrial animals should be separated and not called "wild life" needs to be discussed.

The first textbook was that by Aldo Leopold (1933). There was active wildlife management work published in the U.S. in 1905 and before that. The textbook date is relevant only as a benchmark date.

Wildlife (primarily terrestrial animals (by convention)) is a resource, one among many. By analogy, it is as meaningless to discuss it separately as to discuss the liver of the human body without discussing blood, the cardiovascular system, and the digestive system.

Wildlife management in this course means:

• making decision and acting
• to manipulate the structure, dynamics, and relations
• of wild faunal populations, faunal spaces, and human populations
• to achieve specific, pre-stated human objectives from the faunal resource system.

1. decision making
2. the group of concepts: (1) structure, (2) dynamics, (3) relations
3. wild faunal populations
4. faunal spaces
5. human populations
6. objectives
7. resource systems

1. What courses have you had that are not historical?
2. What was the date of the first U.S. textbook in wildlife management?
3. Write precisely the exact definition of wildlife management as it will be used in this course.
4. List the 7 emphases in the course (so that they will be readily recognized when encountered).

Read: Your Future in Wildlife Management

If wildlife management means making decisions ..., what does this phrase include? I exclude trivial decisions such as whether to get a drink of water or not. There is wonderful philosophy behind what is a decision and whether they exist.

• Future states of a system are based on decisions.
• Decisions can only be made if there are 2 or more alternatives.
• Decisions should be influenced by measures and estimates of accuracy, precision, confidence level, acceptable accuracy, and the power of the tests.

In what priority should we schedule mowing of wildlife clearings in the forest? (Sort then state the sequence)

Is fertilizer treatment A better than treatment B for growing warm-season grasses for quail? (Look: Which is greater? Do a t-test on the results. If the computed "t" is greater than the table value of "t", then there probably is a real difference.

Is there a real difference in the number of female fawns born due to forage changes? Do a chi-square test; the "expected" ratio is 100:100.

On which factors should I do more study? (correlation analyses can be useful)

Decide among who gets permits for blinds? Be fair. Use a random number generator (available in your Capper programs). Is there a global-warming effect on plant A? (Compare the variances before and after some date of interest. Use the F test.)

At what level should I stop irrigating my game bird food plant nursery? At what point should I stop sending brochures? (Use a break-even analysis)

How many more bird-watchers index units will I get if I expand the trail system? Use a simple linear regression procedure; trail lengths on the x-axis.

How can I maximize the profit from 10 species on my area using forestry, rangeland and pasture management, and planned hunting trips, all over the next 50 years? Use optimization procedures such as "linear programming."

Study Guide:

1. What is the difference between accuracy and precision? (i.e., how do you decide? intelligence is defined by some as the ability to discriminate between and among ideas)
2. When is a t-test used? A chi-square test used?
3. Why are 2 or more actions, alternatives, tactics, strategies, or options needed to make decisions?
4. When do you use a t test? a chi-square test? (decide between the two).

We rarely have enough time, money, skills, or other resources in wildlife work to look at all of anything. We need to take samples. There is an elaborate literature on sampling but it is important to know a few basics so that rapid progress can be made (lowering costs) with statisticians. To estimate minimum sample size we need to know how close the answer must be to "perfect truth." How accurate must our estimate of the average value be? We can agree that tons of fish for our wild raptors probably does not have to be as accurate as our measures of workers' head size for our safety-gear studies. If we say that d = proportion of the average (on either side), then it seems logical that the wider this range, the fewer samples we'd need to take. The relationship is inversely proportional to n, the sample size being estimated. We'd expect n = f (1/d). The greater the variance (s-square) the more the samples needed. The greater the confidence you must have in the answer (related by your choice of the alpha level and a value for t) the more samples needed. The relationships are n = s squared x t squared /d squared . Where an average has been found (for a test situation) of 12 and a variance of 16, and when the wildlife manager decides that t can be about 1.7 for large samples and alpha of 0.10, and accuracy level can be plus or minus 0.05, then n = (16) (1.72) / ((12) (0.05))2 = 128. In wildlife work it may not be possible to get 128 samples or to afford analyses on each one at $35 each.

What is the change in n if your relaxed your accuracy requirement to 10% not 5%? The answer:

n = (16) (1.72) / ((12) (0.1))2 = 32

There is a big difference in the costs of processing 32 samples and processing 128. Decisions about alpha levels and risk and accuracy can be very influential. The manager's job is to maximize benefits to a desired level and reduce the costs of units changed.

The manager cannot count as personal success the animals present, only those added (or reduced) above the natural population (or population present when the manager first arrived to begin work.)

This Web site is maintained by R. H. Giles, Jr.
Last revision January 17, 2000.