1. Great Horned Owl: The most common of the three. Has a deep, hooting call that sounds like "hoo hoo hoo."
2. Barred Owl: Also has a hooting call, but it's higher-pitched and more choppy than the Great Horned Owl's. Sounds like "who cooks for you."
3. Northern Saw-whet Owl: Has a call that's more of a tremulous, wavering whistle than a hoot. Sounds like "too too too" or "too too too too too too."