Hawaiʻi creeper is able to climb up and down trees. It uses its short, sharp beak to probe bark for insects residing underneath. If available, it will sip nectar from koa ("Acacia koa") or ōhia lehua ("Metrosideros polymorpha"). The breeding season of the Hawaii creeper lasts from April to July, during which female birds lay one to three eggs. Nests are hidden in a tree cavity or built on a high branch in either a koa ("Acacia koa") or a ōhia lehua ("Metrosideros polymorpha"). Eggs hatch after around thirteen days. The Hawaii creeper was put on the endangered species list in 1975;
Metrosideros polymorpha the most common native tree in the Hawaiian Islands, tolerating a wide range of soil conditions, temperature, and rainfall. It grows from sea level right up to the tree line at elevations of and is commonly found in moist and dry forests, high shrublands, and is a colonizer of recent lava flows. It is relatively slow growing. Dominant in cloud forests above , the tree is also common in seasonally wet forests, where it may be dominant or form mixtures with the native "Acacia koa". "Metrosideros polymorpha" may occur as a tall tree or a prostrate shrub, and everything in