Question

One way to determine the density of animals in an area is to use the mark-recapture technique. A number of individuals from a population are captured, marked so they are easily identifiable, and released back into the population. It's assumed that the captured and marked animals will randomly mingle with the rest of the population. Later, the population is re-sampled and the number of marked and unmarked animals is recorded. The following equation can then be used to estimate the size of the entire population. Gulded S Number of individuals marked in first catch Total population size, N Number of marked recaptures in second catch Total number of second catch If 25 Prairie Dogs were captured, marked, and released back into their population, and then subsequently 135 Prairie Dogs were captured, of which 18 were marked, what is the approximate total population size, N?

Answer 1

The approximate total population size, N = 188 Prairie Dogs

Step-by-step explanation:

The equation of the mark-recapture technique of determining population density is given below:

Number of individuals marked in the first catch/Total population size, N = Number of marked recaptures in second catch/Total number of second catch

If 25 Prairie Dogs were captured, marked, and released back into their population, and then subsequently 135 Prairie Dogs were captured, of which 18 were marked

Number of dogs marked in first catch = 25

Number of marked recaptures in the second catch = 18

Total number of second catch = 135

Substituting the given figures and solving for N, the total population:

25/N = 18/135

18N = 25 × 135

18N = 3375

N = 3375/18

N = 187.5

Thus, the approximate total population size, N = 188 Prairie Dogs