Yellow Tyrannulet

The Yellow Tyrannulet, Capsiempis flaveola, is a diminutive passerine bird belonging to the tyrant flycatcher family. With a length of 10.5-11.4 cm and a weight of a mere 8 grams, it bears a resemblance to a minuscule vireo or warbler. Its plumage is characterized by olive-green upperparts and vivid yellow underparts, while the head is adorned with whitish or pale yellow supercilia. The wings and tail exhibit a dusky brown hue with subtle yellow feather-edging and two yellowish wing bars. Both sexes share a similar appearance, though juveniles display a browner back and a paler yellow belly.

Identification Tips

When identifying the Yellow Tyrannulet, look for its slender build and small bill, which set it apart from other species. The combination of olive-green and bright yellow plumage, along with the distinctive supercilia and wing bars, are key identification markers. The bird's size is also a helpful clue, as it is one of the smaller members within its family.

Habitat

This species thrives in a variety of environments, including thickets, forest edges near streams, dense secondary growth, and bushy pastures or clearings. It is adept at navigating these habitats in search of sustenance and shelter.

Distribution

The Yellow Tyrannulet has a broad range that extends from Nicaragua through to northeastern Argentina and southeastern Brazil. It is a resident breeder throughout this expanse, adapting to various local conditions.

Behaviour

Observed as active and sociable creatures, Yellow Tyrannulets are often seen in pairs or family groups. They exhibit a foraging behavior that includes gleaning insects and spiders from foliage and executing short sallies to capture their prey.

Song & Calls

The vocal repertoire of the Yellow Tyrannulet includes a soft "pewik" call and a rhythmic duetted song that can be described as "pee-tic-keek." Notably, there is some geographical variation in both the bird's appearance and its vocalizations.

Breeding

The Yellow Tyrannulet constructs a cup-shaped nest from plant fiber and grass blades, which is artfully decorated with moss on the exterior. This nest is typically situated 2-7 meters above ground in a tree, shrub, or even a maize plant. The usual clutch consists of two white eggs, which may be unmarked or exhibit very light rufous speckles.

Diet and Feeding

The diet of the Yellow Tyrannulet is composed of insects, spiders, and small berries. Its feeding technique involves actively gleaning from foliage or engaging in brief flights to snatch prey.

Conservation status

The IUCN Red List has classified the Yellow Tyrannulet as Least Concern, indicating that the species currently faces no significant threats to its survival on a global scale.