A large uniform chestnut finch with a robust pink-horn bill. Endemic to São Tomé and very rare; once thought to be extinct. Found singly and in pairs in primary and secondary forest in remote highlands where good habitat persists. Prefers the middle levels of the forest, but is also occasionally encountered on the ground. Loud human-like whistles, upslurred and high-pitched, “weeeooo” or “wheeet-wheeeoo,” are often the first sign of its presence. The Principe seedeater is much smaller and duller in coloration than Sao Tome Grosbeak.