Study Details Endangered Bird's Unique Feeding Anatomy

Researchers examined skeletons of the endangered ʻakiapōlāʻau to understand how the Hawaiian honeycreeper feeds on hidden insects.

Updated on Nov. 5, 2026 in Bird Watching

Screen-print poster illustration of a curved ochre bird bill resting against dark wood with a small excavated hole, set on a flat forest-floor field. — Researchers publishing in the journal Ornithology detailed how the endangered ʻakiapōlāʻau, found only on Hawaii island, uses its skull and bill to extract hidden insect larvae from wood. AI Illustration. Upload story photo >

Researchers published a study in the journal Ornithology describing the anatomy behind the endangered ʻakiapōlāʻau's feeding behavior. The bird, found only on the island of Hawaii, feeds mainly on insects, including larvae hidden in branches.

Why it matters

The ʻakiapōlāʻau is endangered, and understanding how it forages helps explain how the species survives on Hawaii's islands. The findings show how its skull and bill structures are adapted to extracting prey from wood.

The study examined three ʻakiapōlāʻau skeletons from the Museum of Vertebrate Zoology at the University of California, Berkeley, and compared them with related continental finches. The upper bill's underlying bone is about 38% shorter than its outer covering, a measurement the study used to characterize the bird's feeding structure.

The players

Alexander Clark

Clark is a University of Chicago doctoral candidate and scientific affiliate with the Field Museum in Chicago who led the study.

The details

The bird taps a branch to feel for hollow spaces, then gouges the wood with its lower bill while holding the upper bill away. After creating an opening, it inserts its slender upper bill and searches side to side for prey.

Reuters published its article on the study on November 5, 2026.

Season Trajectory

The study fits into a long line of comparative anatomy work on Hawaiian honeycreepers, which have been studied through museum specimens to understand how their bill and skull structures evolved. Its comparison to woodpeckers, which have reinforced bone structures between the eyes, places the ʻakiapōlāʻau within a known pattern of wood-probing adaptation.

For birders visiting Hawaii, the ʻakiapōlāʻau is found only on the island of Hawaii, so the study's findings are relevant to anyone hoping to observe the species in its native habitat. Knowing how the bird feeds may help observers recognize its foraging behavior in the field.

The takeaway

The ʻakiapōlāʻau's feeding anatomy shows how a small bird can evolve tools for extracting insects from wood. Observers in Hawaii can look for the bird's probing behavior on the island of Hawaii.