A researcher wanted to know how many fish were in a dam.He caught 20 fish and marked them by clipping out a small section of their tail fins.He then released them back into dam.A few days later he caught 25 fish and found that 8 had been marked

1.estimate the total number of fish in the dam by using the formular P=FxS/M

Give one reason why the method used by the researcher to mark the fish could have resulted in an inaccurate estimate of the fish population in the dam.

Thanks

Because few days later he caught 8 fish and had been marked

P=f×s÷m

=25×20÷8
=62,5

To estimate the total number of fish in the dam using the formula provided, let's go through each component:

P: Total population of fish in the dam (what we want to estimate)
F: Number of fish initially caught and marked (20)
S: Number of fish caught in the second sample (25)
M: Number of marked fish in the second sample (8)

According to the formula P = F x S / M, we can substitute the values:

P = 20 x 25 / 8

P = 500 / 8

P ≈ 62.5

So, based on this estimation method, there could be approximately 62.5 fish in the dam.

Now, let's discuss a reason why this marking method may result in an inaccurate estimate:

One reason is that the marked fish might have a higher chance of being caught again compared to unmarked fish. This could be due to several factors, such as the marking interfering with their natural behavior, making them more visible or possibly less able to evade fishing gear. As a result, the proportion of marked fish in the re-captured sample might be higher than their actual representation in the total population. This would lead to an overestimation of the fish population in the dam.

It's worth noting that this marking method assumes several assumptions, such as the marked fish mixing randomly with the rest of the population, no mortality or emigration of fish, and similar catchability for marked and unmarked fish. These assumptions may not hold true in all cases and could further contribute to inaccuracies in the population estimate.