[4] There are competing beliefs on who the closest relative to the whistling warbler (Catharopeza) is between Phaeothlypis and Dendroica.

When sorted taxonomically, they are often adjacent due to their similarities in morphology and song.

[4] A bright white ring surrounds the eye, with a hazel iris.

[6][3] There is also an off-white color on a minor portion of the chin and on the ends of feathers on the upper throat.

[3] The tarsus and toes are a light orange color, and they also have a small manubrium-sternum bridge.

[3] The whistling warbler's song has a rapid rhythm, with an increasing intensity that is comparable to the Troglodytes rufescen, with less variation.

They also found that the Whistling Warbler's songs could be heard from morning to late afternoon, unless it was heavily raining.

[4] Whistling warblers inhabit the hills and mountains of St. Vincent island, including Richmond Peak, and Grand Bonhomme.

There is no dry season on the hilltops and they are considered rainforests due to their 3800 mm of rain annually.

[4] The whistling warbler's cup-shaped nests are found at low heights and spotted eggs have been seen in them.

The whistling warbler often flicks this "cocked tail" swiftly when observed foraging.

Both volcanic activity and deforestation for sugarcane have decreased the whistling warbler's population by around 50%.