A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. calculate an estimate of the number of individuals added to (or lost from) a population of 1,000 individuals in one year.

a. 120 individuals added

b. 40 individuals added

c. 20 individuals added

d. 400 individuals added

e. 20 individuals lost

The change in the population is the difference between the annual per capita birth and death rates multiplied by the population. The number of individuals added to the population is 40.

The given parameters are:

[tex]r_1 = 0.06[/tex] ---- annual per capita birth rate

[tex]r_2 = 0.02[/tex] --- annual per capita birth rate

[tex]n = 1000[/tex]

First, we subtract the death rate from the birth rate

[tex]\triangle r = r_1 -r_2[/tex]

[tex]\triangle r = 0.06 - 0.02[/tex]

[tex]\triangle r = 0.04[/tex]

The number of individuals (k) in one year is:

[tex]k = n \times \triangle r[/tex]

So, we have:

[tex]k = 1000 \times 0.04[/tex]

[tex]k = 40[/tex]

Since k > 0, then individuals were added.

Hence, 40 individuals were added to the population of 1000