Answer:
1. The number of individuals added/subtracted from a population of 1,000 individuals in one year = 70/10 respectively (60 net).
2. The size of the entire population of birds = 2,000.
Explanation:
1. Population = 1,000
Birth rate = 0.07
Death rate = 0.01
Population Growth Rate = Birth rate + Net migration - Death Rate
= 0.07 = 0.01
= 0.06
The number of individuals added to the population = 70 (1,000 * 0.07)
The number of individuals subtracted from the population = 10 (1,000 * 0.01)
Therefore, the overall number added = 60 (70 - 10) or (1,000 * 0.06)
2. Number of birds tagged in one month = 300
Number of birds captured after several months later = 500 birds
Number of birds captured with a tag on them = 75
The proportion of tagged birds out of the captured = 75/500 = 0.15
The size of the entire population of birds = Number of birds tagged/Proportion of captured birds with a tag
= 300/0.15
= 2,000
