Treecreepers: Certhiidae

All treecreepers, except for one species, use their tails to help them climb. Their short legs, long toes, and strong claws help them to cling tightly to the side of trees while foraging (searching for food). They forage singly, in pairs, and in flocks of many different bird species. Foraging rituals consist of flying to the base of a tree and then searching and probing under the bark for insects while climbing the trunk. They also look for food while clinging to the undersides of limbs, creeping outward from the trunk almost to the tip of the main branch. They climb in a jerky, spiral motion. Songs of treecreepers are quiet sounding trills, and calls are high-pitched and thin. Such sounds are used to establish and defend their breeding territory.

Most treecreepers construct nests under loose pieces of bark on dying or dead trees. Once in a while, treecreepers build nests on walls of buildings, in crevices (narrow cracks or openings) of trees, in heavy vegetation such as ivy, and within nesting boxes. Nests are built from 1.5 to 52 feet (0.5 to 16 meters) off the ground, with such a range of heights due to differences in species. Most females lay four to six white and faintly spotted red or reddish brown eggs. Females perform all of the incubation (sitting on eggs) duties, but both males and females feed their young. The brooding period (time to raise young together) is thirteen to seventeen days, with sometimes two broods each year. After the young are old enough to fly off, they will often remain as a family group for two to three weeks.