Correct!
Great Horned Owls will also eat porcupines.
No smallish creature is safe. Foxes, turkeys, bats, fish, scorpions, snakes, other owls. You name it and it's around owl size or smaller, an owls will eat it.
Skunk spray isn't great for their eyes though. Here is an owl in with skunk sprayed eyes.
It can cause irritation or ulceration, and then animals will rub at their eyes, potentially causing further physical damage.