Garden Emerald

Chlorostilbon assimilis

Small hummingbird with limited range. Male entirely glittering green with dark forked tail. Bill is straight and all black. Does not have coppery rump like Steely-vented Hummingbird. Female is clean white below with distinctive black cheek and white line behind eye. Nearly identical to Canivet’s Emerald but no range overlap. Found in second-growth, gardens, and forest edge.

Identification

The garden emerald is 7.8 to 8.5 cm (3.1 to 3.3 in) long and weighs about 3 to 4.1 g (0.11 to 0.14 oz). The adult male has dark metallic green upperparts with bluish green uppertail coverts. Its forked tail is blue-black and the central feathers have a light bluish green gloss. Its underparts are a brighter metallic green than the upperparts, sometimes with a light blue sheen, and it has white thigh tufts. The adult female has bright metallic green to bronze green upperparts with bluish green uppertail coverts. Its tail is blue-black, with dull metallic green central feathers and pale gray tips on the outer ones. It has dusky cheeks, a white or grayish white spot behind the eye, and pale gray underparts. Juvenile males are like the adult female but darker gray below.

Taxonomy

The garden emerald was at one time considered a subspecies of the blue-tailed emerald (Chlorostilbon mellisugus). As its own species, it is monotypic.

Scientific name
Chlorostilbon assimilis
Authority
Lawrence, 1861
Order
Apodiformes
Family
Trochilidae
Genus
Chlorostilbon

Range and habitat

The garden emerald is found in southwestern Costa Rica, the Pacific coast of Panama, and the offshore Coiba and Pearl islands. It inhabits open landscapes like the edges of woodlands, hedgerows, streamside thickets, scrublands, and gardens. It is a bird of the lowlands, reaching from sea level to 1,500 m (4,900 ft) in Costa Rica and 1,200 m (3,900 ft) in Panama.

Migration
Resident species

Behavior

The garden emerald is generally sedentary. However, there are reports of its moving back and forth between mainland Panama, the Pearl Islands, and other small islands.<p>The garden emerald forages for nectar by trap-lining, visiting a circuit of flowering trees, shrubs, and other plants. It also feeds on small insects that it gleans from vegetation.<p>The garden emerald's breeding season has not been fully determined but in Panama appears to span at least from November to March. Its nest, incubation length, time to fledging, and other details of its breeding phenology have not been documented. They are assumed to be similar to those of other Chlorostilbon hummingbirds.<p>The garden emerald's vocalizations are not well known but appear to be similar to those of Canivet's emerald (Cynanthus canivetii). That species' song is believed to be "an endlessly repeated, characterless wiry tseee tseeree" and its call has been described as "a dry, scratchy chut or chit, sometimes run together into a soft, staccato chatter".

Conservation

Population trend
stable

Photos

Distribution

Bird Calls

Start Your Bird Watching Journey

Identify a bird outdoors and keep the field guide close for your next observation.