Answer Key for "Population Dynamics" worksheet

1. 131 deer

2.

open field A-67 deer
open field B-50 deer
pine forest I-9 deer
pine forest II-5 deer

3.

a. 30% would be lost
b. 51% would be eliminated
c. They would move to surrounding areas.
d. The carrying capacity of these areas could be exceeded.

4.

a. 1.2% of the deer habitat in open field B will be lost (area lost = 101 feet wide x7,920 feet long = 799,920 feet total area of highway; 799,920 square feet divided by 43,560 feet in one acre = 18.4 acres. 18.4 acres divided by the total land acreage, 1,560 acres = 1.2% of the deer habitat lost in highway development. Another way toobtain this answer is to divide 799,920 square feet by 67,953,600 square feet (the total area in square feet), then multimpy the result by 100 to obtain the percentage.)

b. 2.6 or 3 deer will theoretically be eliminated. (18.4 acres times 500 pounds of forage per year in one acre of open field = 9,200 pounds of forage lost. Divide 9,200 by 3,600 (the amount of forage needed to sustain an adult deer for a year) to determine the number of deer that could be eliminated)

c. A smaller number of deer would be eliminated as pine forest provide less forage per acre. 18.4 acres in pine forest II = 1,288 pounds of forage lost per year. Dividing this figure by 3,600 results in the loss of less than one deer. Remind the students that although the total area of habitat lost is the same in the pine forest as the open field, since the initial carrying capacity of the pine forest is less than the open field, there are fewer deer in the pine forest from the outset, so the impact on the habitat results in less dramatic loss of population. These concepts are frequently included in environmental impact statements that must be filed before many construction projects begin.