Unlike most owls, they have dark eyes. Flammulated owls, also found in the park, also have dark eyes, but they are much smaller than Mexican spotted owls.
These owls have an ashy-chestnut brown coloration with white spots on their breast, back, and head. Their brown tails are marked with thin white bands.
Females are larger than males, standing up to 18 inches (45cm) tall.
Juveniles less than 5 months have a downy appearance.
Mexican spotted owls are found from central Mexico to southern Utah and Colorado.
In most of their range, spotted owls live in old-growth forests. In the Grand Canyon, they live in caves and ledges on the cliffs of narrow side canyons.
They do not build their own nest, but instead use stick platforms made by other birds, tree cavities, cliff platforms, and caves.
Mexican spotted owls are nocturnal, and are most active at night.
The most common prey are rodents, including woodrats, mice, and pocket gophers.
Each pair will have 2-4 eggs per year. Spotted owls are most vocal during mating season and while they are raising their chicks, a period lasting from March through June. During this time of year, their common four-note hoot is heard in the early evening and just before dawn.
Chicks can fly short distances by the time they are 40-45 days old, and begin hunting at around 60-70 days old.