Golden-crowned Emerald

The golden-crowned emerald, Cynanthus auriceps, is a diminutive and radiant hummingbird, measuring a mere 7.5 to 9.5 cm in length and weighing approximately 2.2 grams. The species is distinguished by the adult male's resplendent golden green crown and a body that transitions from a duller golden green to a bronzy hue across the upperparts. The underparts exhibit a gradient from a nearly pure green at the chin and throat to a brilliant golden green at the vent. The tail is a notable feature, long and deeply forked, with black feathers that possess a violet-bluish sheen and broad brownish gray tips on the central three pairs.

Identification Tips

Males can be identified by their red bill with a black tip, while females have a red mandible with a black tip and a black maxilla. Females also have a shorter, forked tail with bluish green to bronze green central feathers, most with a black band near the end and gray tips. Their underparts are light gray, palest on the belly and vent, and they have a grayish white streak behind the eye.

Habitat

This species is native to the tropical dry forests of western Mexico, thriving at elevations from sea level to 1,800 meters.

Distribution

The golden-crowned emerald's range extends from Sinaloa south to eastern Oaxaca and inland along the Balsas River basin to southern Morelos.

Behaviour

The golden-crowned emerald is primarily sedentary, though it may undertake some seasonal elevational movements in certain areas. When feeding, they exhibit a tail-wagging behavior and spread their forked tail.

Song & calls

The vocalizations of the golden-crowned emerald consist of dry, rattling, and chattering calls.

Breeding

Breeding season for this species spans from February to July. The golden-crowned emerald constructs a small cup nest near the tip of a thin branch close to the ground, often with a platform of wood pieces beneath the cup. The nest is crafted from kapok seed fibers, grass, bits of wood, and lichens. Clutch size is typically two eggs, with fledging occurring around 24 or 25 days post-hatching.

Diet and Feeding

Golden-crowned emeralds are "trap-line" feeders, following a circuit of flowering plants to consume nectar. They also forage for insects on foliage.

Conservation status

The IUCN has classified the golden-crowned emerald as Least Concern, with a large range and an estimated population of at least 50,000 mature individuals. The population is believed to be decreasing, but human activity is thought to have little short-term effect on this species.