To find the efficiency of energy transfer between the harbor seal (2,500 Kcal) and a polar bear (375 Kcal), we can use the given formula:
\[ \text{Efficiency} = \left(\frac{\text{Energy level transferred to next level}}{\text{Total energy input}}\right) \times 100 \]
Here, the energy level transferred to the polar bear is 375 Kcal, and the total energy input is 2,500 Kcal (the energy of the harbor seal).
Substituting these values into the formula:
\[ \text{Efficiency} = \left(\frac{375 \text{ Kcal}}{2500 \text{ Kcal}}\right) \times 100 \]
Calculating the fraction:
\[ \frac{375}{2500} = 0.15 \]
Now, multiplying by 100 to get the percentage:
\[ 0.15 \times 100 = 15% \]
So, the efficiency of energy transfer is 15%.