After its discovery in 1897, the teardrop white-eye (Rukia ruki) was long believed to inhabit a microscopic range. Within the Western Pacific, endemic to Micronesia. Within Micronesia to the Caroline Islands. Within the Carolines, to Chuuk Atoll. Within Chuuk, only the Faichuk island group. And within that group, it was known only from the island of Tol, from the summit of its tallest mountain: Winipot.
Dominating the upper canopy of Mount Winipot is the endemic Chuuk poison tree (Semecarpus kraemeri). It produces a highly toxic sap that causes severe allergic contact dermatitis and painful blistering in humans. Historically, this toxic tree shielded Winipotâs native forests from fire and axe â offering sanctuary to the teardrop white-eye.
Unlike most of its white-eye cousins in the Zosterops genus â which are small, yellowish, and difficult to tell apart â the teardrop white-eye is noticeably larger, has sombre olive-brown plumage, and features bright orange legs. Beneath its eyes, it has distinct white feather crescents that look like permanent teardrops.
In the 1980s, surveys estimated that 382 teardrop white-eyes lived on Tol. They also found tiny, restricted populations of the species across a few neighbouring islands. But ârestrictedâ is the key word here: 93 on Polle, 32 on Paata, and just 19 on Onei. Those same surveys estimated that the white-eyeâs total known range was only about one square kilometre, or less than a third the size of Central Park.Â
More recent surveys on neighbouring islands have either turned up empty or been impossible to undertake due to local opposition and other difficulties. We cannot say whether the teardrop white-eye exists anywhere outside of Tol today.Â
There is some hope, however, for the species. A recent birding expedition, undertaken in June 2026, saw at least seven white-eyes creeping along vines and branches in the old-growth forest below Mount Winipot.Â
Read the teardrop white-eyeâs full story here!