<trp-post-container data-trp-post-id='360762'>Mouse-colored Tyrannulet
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En bref
- Scientific Name: Phaeomyias murina
- Spanish Name: Tiranuelo ratón
- Famille : Tyrannidae
- Known Nicknames: Mouse-colored Flycatcher, Mouse-brown Tyrannulet
- Longueur moyenne : 11–12 cm / 4,3–4,7 pouces
- Average Weight: 8–11 g / 0.28–0.39 oz
- Wingspan: 17–20 cm / 6.7–7.9 in
- Key Feature: Drab, uniformly brownish-gray plumage with pale wingbars
- Régime alimentaire principal : Principalement insectivore
- Range: Panama, Colombia, Venezuela, the Guianas, Brazil, Bolivia, Paraguay, Uruguay, and northern Argentina
- Habitat: Tropical dry forests, gallery forests, scrublands, and forest edges
- Structure sociale : Solitaires ou en couples
- Nesting/Breeding: Small cup-shaped nest in a tree fork or shrub
- Statut de conservation : Préoccupation mineure (LC)
- Évolution démographique : Stable
The Mouse-colored Tyrannulet (*Phaeomyias murina*) is a small, unassuming yet fascinating passerine bird found across a wide swath of Central and South America, from Panama to Argentina. True to its name, its general appearance is drab and mousy, with olive-brown upperparts, pale whitish underparts, and a subtle, pale wingbar, making it one of the most challenging tyrant flycatchers to identify by sight. Its unique characteristic lies in its voice and behavior: it is far more often heard than seen, delivering a distinctive, nasal, and slightly insect-like “*pswee-ip*” call from the canopy. A special feature is its surprisingly broad habitat tolerance, thriving not only in mature forests but also in scrublands, savannas, and even urban gardens, where it actively gleans insects from foliage with quick, agile movements, a behavior that sets it apart from many flycatchers that prefer aerial sallies.
Faits amusants
Despite its unassuming name, the Mouse-colored Tyrannulet has a surprisingly aggressive streak, often fearlessly dive-bombing much larger birds like hawks and toucans that stray near its nest. It also possesses a unique vocal quirk: its call, a sharp *psee-weet*, is so high-pitched that it often falls outside the human hearing range, functioning as a secret communication channel among its kind. In a bizarre adaptation, it frequently builds its small, cup-shaped nest directly into the abandoned nests of other, larger birds, using their structure as a ready-made foundation for its own home.
Habitats et répartition
The Mouse-colored Tyrannulet occupies a broad range of open and semi-open habitats across much of South and Central America. It is commonly found in dry scrublands, savannas, forest edges, second-growth woodlands, gallery forests, and arid lowland regions, often avoiding dense, humid rainforest interiors. Its geographical range extends from southwestern Costa Rica and Panama through Colombia, Venezuela, and the Guianas, then south and east across much of Brazil, Bolivia, Paraguay, and northern Argentina, reaching as far as Uruguay. It also occurs on the Pacific slope of the Andes in Ecuador and Peru, and is present on Trinidad and Tobago.
Comportements & Reproduction
The mouse-colored tyrannulet is generally solitary or found in loose pairs, with no complex social structure observed outside of breeding. Mating habits are not extensively documented, but the species is monogamous during the breeding season. The male performs a simple aerial display or song to attract a female, and both parents participate in nest construction, incubation, and feeding. The nest is a small, cup-shaped structure made of plant fibers and spider webs, often placed in a tree fork. Clutch size is typically two eggs, and there is no evidence of cooperative breeding or unique strategies such as brood parasitism. The incubation period lasts about 14–15 days, with fledging occurring around two weeks after hatching.
Alimentation
The Mouse-colored Tyrannulet (Phaeomyias murina) is primarily insectivorous, with a diet consisting almost entirely of small arthropods such as flies, beetles, caterpillars, and spiders, which it actively forages for by gleaning from foliage and making short aerial sallies. An interesting fact about its feeding behavior is that it is a habitual "flush-chaser," often following army ant swarms to capture insects and other arthropods flushed by the ants' movement, allowing it to exploit a concentrated food source. Additionally, while it rarely consumes fruit, it has been observed taking small berries and seeds opportunistically, particularly during the non-breeding season when insect prey is less abundant.
Couleurs
The Mouse-colored Tyrannulet is a small, drab bird with overall brownish-gray plumage, paler on the underparts, and faint wing bars formed by buffy edges on the flight feathers. It lacks bold markings or bright colors, with its uniform, mouse-like hue providing excellent camouflage against tree bark and dry foliage in its scrub and woodland habitats.
Distribution Map
Places linked to this species. A sighting is never guaranteed.
