En bref

• Scientific Name: Xolmis velatus
• Spanish Name: Monjita Rabadilla Blanca
• Famille : Tyrannidae
• Known Nicknames: White-rumped Monjita
• Average Length: 18–20 cm / 7.1–7.9 in
• Average Weight: 30–40 g / 1.1–1.4 oz
• Wingspan: 28–32 cm / 11–12.6 in
• Key Feature: White rump and outer tail feathers contrasting with pale grey upperparts
• Régime alimentaire principal : Insectivore
• Range: Central and eastern South America (Brazil, Bolivia, Paraguay, Argentina, Uruguay)
• Habitat: Open savanna, grasslands, and cerrado with scattered trees
• Structure sociale : Solitaires ou en couples
• Nesting/Breeding: Open cup nest in tree fork or shrub
• Statut de conservation : Préoccupation mineure (LC)
• Évolution démographique : Stable

The White-rumped Monjita (*Xolmis velatus*) is a striking passerine bird native to the grasslands and open cerrado of central South America, most notably Brazil and Bolivia. Its most distinctive feature, as its name suggests, is a brilliant white rump that contrasts sharply with its otherwise soft gray upperparts, white underparts, and a subtle, pale wing patch. This monjita also possesses a unique, almost “hooded” look due to a dark mask across its eyes, set against a pale crown and face. A special behavioral trait is its insect-hawking style: it often perches conspicuously on fence posts or low shrubs, sallying out to snatch flying insects mid-air, and is known for a curious, upright posture that makes it appear perpetually alert. Despite its delicate beauty, it is a hardy specialist of fire-prone and seasonally dry habitats, where its crisp, white rump flashes like a beacon against the tawny landscape.

Faits amusants

The White-rumped Monjita is a master of aerial ambush, often perching motionless on a fence or bush for extended periods before launching a rapid, looping flight to snatch insects mid-air, sometimes returning to the exact same perch. It possesses a quirky, almost comical habit of flicking its wings and tail in a nervous, twitchy manner even when at rest, a behavior thought to flush hidden prey or signal to mates. Remarkably, this species exhibits a unique adaptation for its grassland habitat: it will frequently follow grazing cattle or capybaras, using them as mobile beaters to stir up grasshoppers and beetles, then darting down to catch the fleeing insects—a classic example of commensal foraging. Despite its drab gray-and-white plumage, the male’s bright white rump patch is highly reflective and flashed during courtship displays, creating a stark visual signal against the open pampas.

Habitats et répartition

The White-rumped Monjita primarily inhabits open, semi-arid to arid landscapes, including dry savannas, scrublands, and grasslands with scattered bushes or low trees. It is often found in the Caatinga and Cerrado biomes, favoring areas with sparse vegetation, sandy soils, and occasional rocky outcrops, where it perches conspicuously on fences, posts, or low branches to hunt insects. Its geographical range is restricted to central and eastern South America, occurring mainly in northeastern and central Brazil, with records extending into adjacent parts of eastern Bolivia, Paraguay, and extreme northern Argentina. The species is generally resident but may undertake local movements in response to seasonal conditions or habitat changes.

Comportements & Reproduction

The White-rumped Monjita is generally observed alone or in pairs, particularly during the breeding season, suggesting a socially monogamous mating system. Males establish and defend small territories, often perching conspicuously to advertise ownership and attract a mate. Courtship involves aerial displays with fluttering flights and vocalizations. The nest is a shallow cup built in a tree fork or cavity, constructed primarily by the female from twigs and rootlets. A typical clutch contains two to three eggs, which are incubated solely by the female for roughly two weeks, while the male assists by guarding the territory and bringing food. Both parents feed the altricial young, which fledge after about two weeks. A unique strategy includes the frequent reuse of old nests from other bird species, such as ovenbirds, which reduces construction effort and may provide better concealment.

Alimentation

The White-rumped Monjita is primarily an insectivorous bird, with its diet consisting almost entirely of arthropods such as beetles, grasshoppers, crickets, and caterpillars. It employs a sit-and-wait foraging strategy, perching conspicuously on exposed branches or fence posts before sallying out to capture prey in mid-air or by dropping to the ground. Interestingly, despite its small size, this monjita has been observed taking relatively large insects, including dragonflies and large orthopterans, and it occasionally supplements its diet with small spiders. Unlike some related tyrant flycatchers, it rarely consumes fruit or seeds, making it a strict carnivore within its open grassland and savanna habitats.

Couleurs

The White-rumped Monjita has pale gray upperparts, a white rump, and a white belly, with black flight feathers and a black tail tipped in white. Its head is light gray with a subtle white supercilium, and the bill is black. This subtle gray-and-white pattern provides camouflage against open, dry scrub habitats by breaking up its outline in bright sunlight.

Distribution Map

Places linked to this species. A sighting is never guaranteed.

Détails de l'attraction

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