Garden Emerald

Chlorostilbon assimilis

Order: Apodiformes / Family: Trochilidae

Wikimedia Commons

green small tropical forest feeder year-round common central-america pollinator

About the Garden Emerald

The Garden Emerald, scientifically known as Chlorostilbon assimilis, is a small yet striking hummingbird that captures the fascination of bird enthusiasts and scientists alike. This species is predominantly found in the lush regions of Central America, particularly in the forests of Costa Rica and Panama. The bird's shimmering green plumage, which gives it its name, serves not only as a display of beauty but also as a tool for communication and camouflage among the dense foliage. The Garden Emerald plays a crucial ecological role as a pollinator, visiting a variety of flowering plants and thus facilitating cross-pollination. This interaction is vital for the biodiversity of the habitats it frequents, such as tropical and subtropical moist forests, where it thrives alongside numerous other species. During the breeding season, the Garden Emerald becomes more territorial, often observed vigorously defending its chosen feeding areas from intruders. This behavior ensures its access to adequate resources to support itself and its offspring. The significance of Chlorostilbon assimilis extends beyond its visual appeal. As an integral part of its ecosystem, it influences the structure and composition of plant communities. This, in turn, sustains a diverse range of organisms that rely on these plants for survival. The Garden Emerald's adaptability to human-altered landscapes also highlights its resilience, as it can often be found in gardens and plantations where flowering plants are abundant. Despite this adaptability, the species faces challenges from habitat loss due to deforestation and climate change, which threaten its natural habitats and food sources. Seasonal behaviors of the Garden Emerald include slight altitudinal movements in response to food availability, although it is not considered a migratory species. During the dry season, it may descend to lower elevations where flowers are more abundant, while in the wet season, it can be found at mid-elevations, taking advantage of the rich floral resources. As a testament to its ecological importance and adaptability, the Garden Emerald continues to be a subject of study for ornithologists and conservationists who seek to understand and preserve the delicate balance of its tropical habitats.

The Garden Emerald belongs to the family Trochilidae, within the order Apodiformes. These birds typically live average 4-6 years, with a maximum of around 9 years..

How to Identify a Garden Emerald

Identifying the Garden Emerald involves observing its distinct iridescent green plumage, which covers its head, back, and flanks. Both males and females possess this vibrant color, although males typically exhibit a more intense sheen. Adult males also have a slightly forked tail with darker, bluish tips, while females display a more rounded tail with white tips. Juvenile Garden Emeralds resemble females but tend to have a duller overall appearance. This small hummingbird measures about 8 to 10 centimeters in length, with a wingspan of approximately 11 to 12 centimeters. Its bill is slender and slightly curved, ideal for accessing nectar deep within flowers. In flight, the Garden Emerald's rapid wingbeats produce a characteristic humming sound, and its silhouette is marked by long wings and a compact body. While perched, it often holds an upright posture, showcasing its vibrant colors against the backdrop of the foliage. This species can be confused with similar hummingbirds like the Canivet's Emerald or the Fork-tailed Emerald, but its particular shade of green and tail shape help in distinguishing it. Observers should note the consistency of the green plumage and the specific tail markings to accurately identify the Garden Emerald.

Having trouble telling birds apart? Upload a photo to our bird identification tool for an instant species match.

Garden Emerald Habitat and Range

Preferred Habitat

The Garden Emerald thrives in various habitats, predominantly favoring tropical and subtropical moist forests. It is most commonly found in lowland and mid-elevation regions, up to about 1,500 meters above sea level. This hummingbird is adaptable and can occupy secondary forests, plantations, and gardens where flowering plants are plentiful. It demonstrates a preference for areas with abundant nectar sources, such as heliconias and other native flora. During different seasons, the Garden Emerald may shift habitats slightly, moving to lower elevations in search of flowers during dry periods. While it is less common in urban settings, it can still be seen in gardens and parks where suitable feeding opportunities exist. The interplay between its natural forest habitat and human-influenced landscapes showcases its ability to survive in a changing environment.

Geographic Range

The Garden Emerald is primarily found in Central America, with its range extending from southern Nicaragua through Costa Rica and into western Panama. It occupies a relatively narrow corridor along the Caribbean slope and adjacent lowlands, where it favors moist forest environments. Although it does not undertake long-distance migrations, this species may exhibit local movements in search of food resources, particularly in response to seasonal changes in flower availability. Within Costa Rica, the Garden Emerald is considered a common resident in suitable habitats, with population densities higher in areas where flowering plants are abundant. In Panama, its presence is similarly noted in regions that offer rich nectar sources, contributing to the overall distribution and population stability of the species.

Want to know which birds visit your area? Browse our backyard birds by location guides for region-specific species lists.

What Does the Garden Emerald Eat?

The diet of the Garden Emerald primarily consists of nectar from a variety of flowering plants. It favors tubular flowers that accommodate its slender bill, such as those of the Heliconia and other native species. This hummingbird also consumes small insects and spiders, which provide essential protein, especially during the breeding season. The Garden Emerald employs a hovering technique to feed, allowing it to access nectar while remaining in mid-air. It forages throughout the day, with peak feeding activities occurring during the early morning and late afternoon when flowers produce the most nectar. Seasonal changes influence its diet, as the availability of different flowers fluctuates, prompting slight shifts in feeding locations and plant preferences.

Want to attract Garden Emeralds to your yard? See our recommended feeders and seed types for the best results.

Garden Emerald Behavior and Social Structure

The Garden Emerald displays a range of behaviors that reflect its adaptability and ecological role. It is generally solitary, except during the breeding season when it becomes more territorial. Males establish feeding territories that they defend aggressively against other hummingbirds and potential intruders. Courtship displays involve elaborate aerial maneuvers and vocalizations to attract females. While not typically forming large flocks, the Garden Emerald may occasionally be found in loose aggregations around abundant food sources. Its response to predators includes rapid evasive flight and the use of cover provided by dense foliage. Daily activities center around feeding, with intervals of rest and preening. During the hottest part of the day, it seeks shade and reduces activity to conserve energy.

Garden Emerald Nesting and Reproduction

The nesting habits of the Garden Emerald involve building a small, cup-shaped nest made of plant fibers, spider silk, and lichen. These nests are typically situated on horizontal branches or within dense foliage, providing camouflage and protection. The female is solely responsible for constructing the nest, incubating the eggs, and caring for the young. Clutch size usually consists of two white eggs, which she incubates for approximately 14 to 16 days. After hatching, the chicks remain in the nest for about 20 to 22 days before fledging. The Garden Emerald typically raises one to two broods per year, depending on environmental conditions and food availability. Parental care continues for a short period after fledging, during which the female feeds and protects the young until they are fully independent.

Garden Emerald Sounds and Vocalizations

The vocalizations of the Garden Emerald are characterized by high-pitched, rapid series of notes that often serve as contact calls or territorial signals. Its song consists of a fast-paced, metallic trill that can be heard during courtship displays and when defending feeding territories. Alarm calls are sharp and slightly harsher, alerting other birds to potential threats. During the dawn chorus, the Garden Emerald becomes more vocal, contributing to the symphony of sound typical of tropical forests at first light. Its calls and songs, though not as melodious as those of songbirds, play a crucial role in communication and territory establishment.

Interesting Facts About the Garden Emerald

1The Garden Emerald can beat its wings up to 80 times per second, allowing it to hover effortlessly while feeding.
2With a heart rate that can reach up to 1,260 beats per minute, the Garden Emerald is one of the most energetically active birds.
3Despite its small size, the Garden Emerald can travel significant distances within its territory in search of food.
4Researchers have observed the Garden Emerald using its iridescent plumage to communicate with other hummingbirds through subtle color changes.
5The Garden Emerald's metabolic rate is among the highest of any vertebrate, requiring constant feeding throughout the day.
6This hummingbird species plays a crucial role in pollinating over 150 species of plants in its native range.
7The Garden Emerald can enter a state of torpor, a temporary hibernation-like state, to conserve energy during cold nights.

Garden Emerald Conservation Status

The Garden Emerald is currently listed as Least Concern by the IUCN, with a stable population trend. However, habitat loss due to deforestation and agricultural expansion poses ongoing threats. Conservation efforts focus on preserving natural habitats and promoting sustainable land-use practices. Historically, the species has maintained a fairly stable population, although local declines have been noted in areas experiencing significant environmental change. Continued monitoring and habitat protection are essential to ensure the long-term survival of the Garden Emerald and its ecological role as a pollinator in Central American ecosystems.

Attracting Garden Emeralds to Your Feeder

The Garden Emerald is a regular visitor to backyard bird feeders across its range. At the Eye On The Fly feeding station, we observe Garden Emeralds regularly and capture footage with our feeder cameras.

Watch Feeder Videos Recommended Feeders