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;
Acacia koa used by ancient Hawaiians to build "waa" (dugout outrigger canoes) and "papa hee nalu" (surfboards). Only "paipo" (bodyboards), "kikoo", and "alaia" surfboards were made from koa, however; "olo", the longest surfboards, were made from the lighter and more buoyant "wiliwili" ("Erythrina sandwicensis"). The reddish wood is very similar in strength and weight to that of Black Walnut ("Juglans nigra"), with a specific gravity of 0.55, and is sought for use in wood carving and furniture. Koa is also a tonewood, often used in the construction of ukuleles, acoustic guitars, and Weissenborn-style Hawaiian steel guitars. B.C. Rich used koa on some