Question

A population of fish has 11,140 individuals. They have a death rate of 100 per year and a birth rate of 120 per year. Assuming 50 fish migrate into the population and 25 migrate out of the population per year, how many individuals would there be after the first year

Answer 1

11,185 individuals

Step-by-step explanation:

The number of individuals after the first year would be 11,185.

The change in the number of individuals in a population or population size is determined by the equation:

(B - D) + (I - E), where B = birth rate, D = death rate, I = immigration, and E = emigration.

In this case, B = 120, D = 100, I = 50, E = 25. Hence, change in the population size;

= (120 - 100) + (50 - 25) = 45

This thus means that the population would have increased by 45 individuals after the first year. Since there were 11,140 individuals initially, the total number of individuals after the first year would be;

11,140 + 45 = 11,185 individuals.