High in the canopy, a flash of black and white catches your eye. It darts and weaves, a tiny zebra flitting through the emerald leaves. This isn’t a hallucination brought on by the Costa Rican rainforest’s magic; it’s the Black-and-white Warbler, a captivating resident gracing our mountain retreat.
A Striking Songbird
Unlike its vibrantly colored warbler cousins, the Black-and-white Warbler (Mniotilta varia) boasts a starkly contrasting plumage. Bold black stripes adorn its entire body, broken only by two prominent white wing bars. Males sport a black bib and cheek patch, while females and juveniles are slightly paler, with a touch of buff on their flanks.
A Nuthatch in Warbler’s Clothing?
Keen observers might notice the Black-and-white Warbler’s unique foraging technique. Unlike most warblers that flit from branch to branch, this little acrobat acts more like a nuthatch. It creeps vertically along tree trunks and branches, its strong legs and long, curved claws providing excellent grip. Its sharp eyes scan the bark for hidden insects, which it gleans with its pointed bill. This behavior earned it the historical nickname “Black-and-white Creeper.”
A Voice Like a Squeaky Wheel
While the Black-and-white Warbler’s attire might steal the show, listen closely, and you might be rewarded with its distinctive song. Imagine a high-pitched, thin whistle, almost like a squeaky wheel. This simple melody, repeated persistently, is a sure sign this fascinating warbler is nearby.
A Seasonal Visitor
Our mountain retreat is a haven for the Black-and-white Warbler during its winter migration. Breeding in northern and eastern North America, these birds journey south from September to April, finding refuge in the diverse ecosystems of Costa Rica. They favor mature deciduous and mixed forests, making our lush mountain slopes their ideal winter home.
A Ground-Nesting Surprise
Despite its acrobatic skills in the trees, the Black-and-white Warbler surprises us with its nesting habits. Unlike most warblers that build nests high in branches, this little zebra prefers to nest on the ground, often at the base of a tree. This strategy might seem risky, but the dense undergrowth in our rainforests provides excellent camouflage for their nests.
A Bird for All Seasons (Almost)
While the Black-and-white Warbler graces our mountain retreat during the winter, birders venturing to Costa Rica’s other regions might spot them in different habitats during migration. They become more generalist in their habitat use outside the breeding season, adapting to a wider range of woodlands and even venturing into shrublands.
A Bird to Remember
Whether you encounter the Black-and-white Warbler flitting through the mountain trees or hear its squeaky serenade, its striking appearance and unique behaviors will leave a lasting impression. So, keep your eyes peeled and your ears tuned; you might just catch a glimpse of this captivating zebra of the Costa Rican skies.
For more information, please view our comprehensive guide about the birds of Costa Rica
