The following text is for questions 9 to 12.

    Burrowing owls are small owls with long legs and short tails. The head is rounded and does not have ear tufts.

    Adults are brown birds mottled with sandy-pale spots on the upperparts. The breast is spotted, grading to dark brown bars on the belly. They have a bold white throat and eyebrows, and yellow eyes. The brown juveniles are less mottled than adults, with buffy-yellow underparts and wing patch.

    Burrowing owls spend most of their time on the ground or on low perches such as fence posts. They hunt close to the ground catching insects and small animals. When alarmed they jolt their bodies quickly up and clown. They are active during the day.

    Burrowing owls live in open habitats with sparse vegetation such as prairie, pastures, desert or shrubsteppe, and airports. In parts of their range they are closely associated with ground squirrels, whose burrows they use for nests.

(Adopted from: https://wwwallaboutbirds.orgiguide/ Burrowing_OwVid (April 4, 2020))

Which part of the bird that change when they become adult?