The eastern chat-tanager is very similar to its sister species, the western chat-tanager (Calyptophilus tertius). Both are brown on top and mostly white underneath, have yellow at the bend of the wing, and both have a distinctive yellow patch in front of the eye that is exposed when the bird is stressed or acting aggressively. However, the eastern chat-tanager is somewhat smaller, has somewhat brighter plumage and has a broken yellow eye ring, while the western chat-tanager as no eye-ring at all. The long, straight, rounded tail of both chat-tanagers reminds us of a mockingbird, while its strong legs recall a thrush.
These traits confused some of the first experts classifying this species, with some placing them in the Mockingbird family (Mimidae), and others in the thrush family (Turdidae). Today, along with its sister species, the eastern chat-tanager is classified within the tanager family (Thraupidae), in their very own genus: Calyptophilus. Whereas the western chat-tanager, has been reported only from the high mountains, above 750 meters, the eastern chat-tanager has a broader range, from sea level, to as high as 2,000 meters.
Although its scientific name suggests a fruit based diet (C. frugivorus), the eastern chat-tanager feeds mainly on invertebrates such as centipedes, butterflies, ants, spiders and some seeds. It forages by searching for prey as it walks stealthily through the leaf litter or near the ground, in dense vegetation. It is a shy bird, often difficult to observe without using audio playback of its song – which typically incites a fierce response in defense of its territory. Their nests have not yet been des cribed, but they are suspected to be similar to those described for western chat-tanager: a large, coarsely-built structure in the form of a partially covered bowl. Its melodious song is very similar to that of the western chat-tanager with very slight variations, consisting of an emphatic and clear whistle chip-chip-swerp-swerp-swerp or chirri-chirri-chirri-chip-chip-chip, repeated multiple times.
“... we played the tape, and in less time than it takes to say it, a furious bird came out of the vegetation. He perched on a low branch and gave his melodious song with such force, in such emphatic tones, that we realized he was defying an intruder. “ Anabelle Stockton de Dod
The distribution of the two species of Calyptophilus chat-Tanagers appears to be a legacy of the configuration of the two paleo-islands that joined to form Hispaniola, with eastern chat-tanagers present to the north-northeast of the Neiba Valley/Cul de Sac Plain and the western chat-tanager, to the South of this depression. Currently, the eastern chat-tanager resides in the mountains of Cordillera Central, Sierra de Neiba and Sierra de Martín García. Historically, it was also in the lowlands of the northeast of the Dominican Republic (Samaná peninsula – Cotuí – Villa Riva) and the island of Gonave, Haití. The eastern chat-tanager’s extirpation at these last two localities reflects the dire extinction threat this species is facing. The extensive deforestation in Sierra de Neiba in recent decades has greatly reduced one of its few remaining strongholds. For all these reasons, the eastern chat-tanager is listed as endangered in the Dominican Republic’s Red List of threatened species. Only the most remote areas of Cordillera Central and Sierra de Martín García may be the last refuge for this rare Hispaniolan endemic bird.