I know it may not be super fair balance-wise, but I like the owl being silent.
Did you know that owls are the quietest hunting birds IRL? They have special branching comb-like serrations on the leading and trailing edges of their wings that during intermediate Reynolds number flow regimes (mid-flight) collapse the no-slip boundary region. This makes them slip through the air quietly.
Now, does this mean the spirit owl in the game should be silent? Well, maybe not for balance reasons. But the owl being silent while hunting makes me happy.