Grauastrild Estrilda troglodytes

A tiny finch of dry grasslands, thickets, and grassy woodlands. Similar to Common Waxbill, but note black rump, unbarred back, white (not dark) undertail, and square-tipped tail. Sexes are similar, but males have a faint pink wash on the underparts that females lack. Gives various nasal and rasping calls; song is two note ‘chee-churr!’. Native to Africa and introduced to several Caribbean islands, Japan, Spain, and the Hawaiian islands (apparently now extirpated).