Question

A random sample pulled 43 catfish from a large lake. They were marked and released. A second sample pulled out 88 catfish. Seventeen had been marked. Calculate the estimated population.

Answer 1

Answer-

Estimated catfish population in that lake is 223.

To calculate the population of moving animals, Mark- recapture technique is used. In this technique some animals are captured from a particular area, then they are marked with tags and released. After some days these animals are again captured in a random way. Among these captured animals, there are some previously marked animals. The total population is being calculated with the help of this data.

Calculation is given below:

Number of marked animals =M Total population size =N Total number of animals recaptured = R Total number of marked animals recaptured = m. According to mark - Recapture technique N -R M = m m N = RXM m Here, R=88 M = 43 m = 17 N= 88 X43 17 - 222.59 ~ 223 Estimated catfish population in the lake = 223