Hihi are sexually dimorphic and dichromatic medium sized forest dwelling passerines. Males are 30% heavier than females, and have a jet black head and a broad band of bright yellow plumage on the shoulders and wing. Males also have white ear tufts which they can erect as a sign of dominance. Females are contrastingly more subtle with a mixing of olives and browns. Both sexes have a dominant white patch in the wings.
Hihi have a large repertoire of vocalizations. Perhaps the most distinctive is their strident call which has been noted to have a fanciful resemblance to the word “stitch” and hence their English name – stitchbird. In addition the males also make powerful high pitched single, double (“tee–cee”) and triple note calls (“tee–cee–VEE”) and both sexes have a low warbling song which can last for several minutes.
Hihi feed on nectar, fruit and invertebrates, the proportions of which vary with availability and time of year. Although no longer considered honeyeaters (see below), they do share a largely overlapping niche with New Zealand’s two honeyeater species, the tui and bellbird (korimako). Both these species are competitively dominant and frequently exclude hihi from fruit and nectar sources. Unlike the tui or bellbird, the hihi has become extinct from most of its former range (see below) and it’s likely that the only remaining natural population exists because of the pristine nature of the habitat there. Consequently, re-establishing a self-sustaining population in coexistence with tui and bellbird is considered an acid test for ecological restoration in New Zealand.
Text by: John G Ewen & Rose Thorogood