Given that the frequency of color blind females is 1 in 25000, calculate the expected frequency of female carriers using the Hardy-Weinberg principle.

Color blindness is an X-linked recessive trait. For females, the genotypes are $X^C X^C$ (normal vision), $X^C X^c$ (carrier), and $X^c X^c$ (color blind). According to the Hardy-Weinberg principle, if $p$ is the frequency of the dominant allele ($X^C$) and $q$ is the frequency of the recessive allele ($X^c$), then the frequency of color blind females ($X^c X^c$) is $q^2$.

The frequency of color blind females is given as 1 in 25000.

To find $q$, take the square root of $q^2$:

Using the Hardy-Weinberg equation $p + q = 1$:

Female carriers have the genotype $X^C X^c$. Their frequency in the population is given by $2pq$.

Rounding to five decimal places, the expected frequency of carriers is 0.01257.

The expected frequency of the carriers of this allele in the population is approximately $\boxed{0.01257}$.