Grey-cheeked

En bref

Migratrice

• Scientific Name: Catharus minimus
• Spanish Name: Zorzal carigris

The Grey-cheeked Thrush (*Catharus minimus*) is a reclusive master of long-distance migration, famously traveling from the remote subarctic boreal forests to the lush basins of South America. This medium-sized songbird is defined by its understated elegance, sporting olive-brown upperparts and a pale underbelly heavily dappled with dark, triangular spots across the breast. Its most namesake feature is the subtle grayish wash on its face and cheeks, which lacks the bold, buffy eye-ring found in similar thrush species. More often heard than seen in its dense, shrubby habitats, the Grey-cheeked Thrush possesses a haunting, flute-like song that spirals downward in a metallic trill, adding a sense of ethereal mystery to the damp northern thickets it calls home.

Faits amusants

The Grey-cheeked Thrush is an elite endurance athlete, with some individuals traveling over 4,000 miles from South America to the Siberian tundra, making it the only North American spotted thrush to regularly breed in the Palearctic. To survive these marathon flights, they can nearly double their body mass in fat during brief stopovers. They are strictly nocturnal migrants, navigating by the stars and Earth’s magnetic field, often letting out high-pitched "peep" calls to stay in contact with other birds in the dark. On the ground, they exhibit a quirky "wing-flicking" behavior when agitated and are so elusive that they are frequently identified only by their ethereal, spiraling song that sounds like it is being played through a flute.

Habitats et répartition

This species breeds across the northernmost reaches of North America, from Alaska through the Canadian boreal forest to Newfoundland, extending across the Bering Strait into northeastern Siberia. It primarily inhabits dense, stunted coniferous forests, taiga, and thickets of alder or willow near the arctic tree line. These birds favor remote, damp environments characterized by low-growing vegetation and scrubby, high-latitude woodlands during the summer months. As a long-distance migrant, it travels through central and eastern North America to reach its wintering grounds in northern South America, primarily within the Amazon basin and the foothills of the Andes. During the winter, it occupies lowland tropical rainforests and mature secondary growth. Throughout its migratory transit, it can be found in a variety of wooded habitats, including deciduous forests, suburban parks, and dense riverside thickets.

Comportements & Reproduction

Primarily solitary and secretive, this species maintains a territorial social structure during the breeding season, where males use ethereal, spiraling songs to define boundaries and attract mates. While they may join loose, itinerant flocks during their extensive nocturnal migrations, they remain largely independent foragers, scouring the leaf litter for invertebrates. Their behavior is characterized by a cautious, skulking nature, often remaining hidden within the dense thickets of boreal and montane forests. Reproduction follows a monogamous pattern, with pairs established quickly upon arrival at high-latitude nesting sites. The female constructs a sturdy cup nest of moss and mud, typically positioned low in scrubby vegetation or on the ground. To navigate the constraints of a short subarctic growing season, they employ an accelerated reproductive strategy: eggs are incubated for less than two weeks, and the young fledge remarkably fast, often within nine to twelve days. Both parents contribute to the intensive feeding of the nestlings, ensuring they reach independence before the demanding southward journey begins.

Alimentation

The Grey-cheeked Thrush maintains a seasonally shifting diet that primarily consists of insects and small invertebrates during the breeding season, transitioning to a heavy reliance on fruits and berries during migration and winter. While on their northern breeding grounds, these birds forage on the forest floor, flipping over leaf litter to uncover beetles, ants, caterpillars, and spiders. An interesting aspect of their foraging behavior is their adaptability; during their long-distance migration to South America, they consume high-energy fruits like elderberries and wild cherries to fuel their flight. In their wintering habitats, they have been observed following swarms of army ants to snatch up fleeing insects, a behavior more common among resident tropical species than migratory ones. This opportunistic approach allows them to thrive across diverse ecosystems, balancing protein-rich prey with carbohydrate-heavy plant matter depending on their immediate energetic needs.

Couleurs

The Grey-cheeked Thrush features uniform olive-brown upperparts and white underparts with a buff-tinged breast marked by dense, dark spotting. Its namesake greyish face lacks a distinct eye-ring, providing a muted appearance that serves as effective camouflage within the dense, shaded undergrowth of its forest habitat.