A random sample of 180 individuals in a population were captured, marked, and released. After a few weeks, a second set of 44 individuals was collected. Out of these 44 individuals, 7 were marked. The estimated population size would be:

Correct option is B

1. Method Used: Lincoln-Petersen Index The formula for estimating the population size (N) using the mark-recapture method is:

Where:
· M =180 (Number of marked individuals in the first sample)
· C = 44 (Total number of individuals in the second sample)
· R = 7 (Number of marked individuals recaptured in the second sample)
Calculation: Substituting the given values:

Rounding to the nearest whole number gives 1131.
Information Booster: 1. Applications of Mark-Recapture Method:
· Estimating populations of wildlife in forests, oceans, and rivers.
· Monitoring population trends of endangered species.
2. Assumptions for Accuracy:
· The population is stable during the study.
· The marks are durable and do not affect the behavior or survival of individuals.
· Sampling is random and unbiased.
3. Potential Sources of Error:
· Overestimation or underestimation if the marked individuals are easier or harder to recapture.
· Population changes due to migration, birth, or death during the study.
4. Other Techniques for Population Estimation:
· Quadrat Sampling: For immobile populations like plants.
· Distance Sampling: Uses observed distances to estimate densities.