Answer: Yes, this fable definitely has a moral that an individual should not be judged based on the things he can't accomplish, but, rather on his talents.
Explanation: This fable clearly criticises our education system using animals as a representation of us humans. The duck, the rabbit and the squirrel are instances where they were suppressed of their natural talents. The eel on the other hand was only average on every subject so had a better average than others whereas that doesn't prove he was better than the duck in swimming or the rabbit in running or the squirrel in flying. Hence, we should focus on the talents we possess and work hard on them rather than on something useless to you.