Fork-tailed Woodnymph

Identification

The fork-tailed woodnymph is a small hummingbird belonging to the "emeralds" group. Males measure 9.5 to 12.9 cm in length and weigh 3.6 to 6 g, while females are slightly smaller at 8 to 10.7 cm and 3 to 5 g. Both sexes possess a straight, black, medium-length bill. The species displays remarkable sexual dimorphism and considerable variation across its thirteen recognized subspecies.

In the nominate subspecies, adult males exhibit dark bronzy-green upperparts with a distinctive violet band across the upper back, a glittering green throat, violet belly, and dark steely-blue undertail coverts with dull white edges. Their most distinctive feature is a forked, blue-black tail. Adult females are brighter green above with a duller, more bronze crown, pale gray underparts, and a green tail base transitioning to steely blue-black with white-tipped outer feathers. Other subspecies show considerable plumage variation, including differences in gorget color, the presence of black bands, and undertail covert coloration, making field identification challenging across the species' range.

Range & Habitat

The fork-tailed woodnymph is found across mainland South America except in Chile and Uruguay, with thirteen subspecies occupying distinct regions from northeastern Venezuela through the Guianas, the Amazon basin, and into parts of Argentina. The species inhabits a variety of Amazonian landscapes, from terra firme and várzea forests to mature secondary forest, forest edges, and gaps. It also frequents semi-open areas including plantations and gardens, and possibly some scrublands. Elevations range from sea level to approximately 2,000 m.

Behaviour & Diet

The fork-tailed woodnymph is assumed to be mostly sedentary, though it apparently makes local movements to follow flowering events. Populations in the Andean foothills may undertake elevational movements. The species forages for nectar at all levels of its habitat, displaying the typical feeding behavior expected of hummingbirds adapted to diverse microhabitats.

Best Time & Places to See It

Specific timing recommendations for viewing this species are not well documented, though flowering events likely influence local availability. Given its wide distribution and habitat preferences, the fork-tailed woodnymph can be encountered across much of tropical South America. Birders exploring terra firme forests, forest edges, secondary growth areas, and gardens throughout the Amazon basin and beyond have good opportunities to encounter this species, particularly in regions corresponding to its recognized subspecies ranges.

Photography Tips

Photographing fork-tailed woodnymphs presents typical hummingbird challenges: their small size, rapid movement, and preference for high canopy levels and mid-story feeding zones require fast shutter speeds and patience. Males' iridescent plumage—particularly the glittering green throat and violet body patches—demands careful attention to lighting angles to capture their full brilliance. The forked tail is a key identifying feature worth emphasizing in images. Subspecies variation means that detailed documentation of plumage patterns, particularly throat and undertail covert coloration, aids both identification and scientific record-keeping.