Oaxaca Hummingbird

The Oaxaca hummingbird, also known as the blue-capped hummingbird (Eupherusa cyanophrys), is a diminutive and vibrant bird, measuring a mere 10 to 11 cm in length and tipping the scales at a lightweight 4.1 to 5.4 grams. This species is distinguished by its straight black bill and sexually dimorphic plumage. The male boasts a violet-blue forehead, a turquoise crown, and emerald green upperparts, with a distinctive rufous patch on the folded wing. The female, while sharing the green upperparts and wing patch, has a more subdued palette with pale gray underparts.

Identification Tips

When attempting to identify the Oaxaca hummingbird, look for the male's glittering green underparts and white undertail coverts, as well as the green central tail feathers and whitish outer pairs. The female can be recognized by her green central tail feathers and white outer feathers with dusky green markings.

Habitat

This species is endemic to the humid montane, semi-deciduous, and pine-oak forests on the Pacific slope of the Sierra Madre del Sur in southern Oaxaca, Mexico. It thrives at the edges and interiors of these forests.

Distribution

The Oaxaca hummingbird is a rare jewel, found solely within the Sierra Madre del Sur, also known as Sierra de Miahuatlán, in southern Oaxaca.

Behaviour

While the details of the Oaxaca hummingbird's movements remain somewhat enigmatic, it is suspected that they may undergo seasonal elevational migrations.

Feeding

The Oaxaca hummingbird is known to forage for nectar across various forest strata, from the understory to the canopy. It frequents flowers of Inga, Lobelia, Malvaviscus, and Psittacanthus, among others, and is presumed to supplement its diet with small arthropods.

Breeding

Our knowledge of the Oaxaca hummingbird's breeding habits is limited. However, nests have been observed in May, October, and November, constructed as mossy cups lined with plant down and adorned with lichen on the exterior. These nests are typically situated between 1.2 and 5.4 meters above the ground, and the clutch generally consists of two eggs.

Song & calls

The male's song is a high, rapid warble, somewhat akin to the white-tailed hummingbird's melody but with a jerkier, less hurried cadence. The calls of this species, though not thoroughly documented, are believed to resemble the white-tailed's liquid to slightly buzzy, rolled chip.

Conservation status

The Oaxaca hummingbird is currently classified as Endangered by the IUCN. With an estimated population of 600 to 1700 mature individuals, the species is facing a decline due to habitat destruction and deforestation for agricultural purposes. Despite this, it remains fairly common in areas where its habitat is undisturbed.