This small, greenish-yellow songbird can be found among the boreal, or forests of the northern U.S. and Canada, singing its buzzy "zee-zee-zee-zooo-zeet" song from the treetops.

Physical Description

Small for a songbird, with a thin, pointed bill and long black legs. They can be identified by their olive green and bright yellow feathers on their head and back, and black-and-white wings. Males have black throats and gray underbelly plumage; females have lighter coloring on their throats and black markings on their chest. 

Size

Around 4.3–4.7 inches (11–12 centimeters) long. They weigh between 0.3–0.4 ounces (8.5–11.3 grams), about the same weight as two nickels.

Native Habitat

Deep inside northern forests with a mix of coniferous and broad-leafed trees. They make migratory stops in wooded areas and winter among mountain forests.

Lifespan

The oldest bird on record lived for about 6 years, lifespan otherwise unknown.

Communication

Males sing to establish their territory and attract females during the breeding season. 

Food/Eating Habits

Black-throated green warblers fly quickly among the trees in search of insects to eat, often hovering to pluck their prey from the undersides of leaves. They also eat berries sometimes.

Sleep Habits

Black-throated green warblers are active during the daytime, but they are nighttime migrants.

Reproduction and Development

Males are the first to arrive at the forest breeding grounds, claiming their territory through song and by repelling other males until the females arrive a week later. Males and females work together to build cup-shaped nests made from twigs and grasses, usually in conifer trees and often fairly close to the ground. Females lay three to five eggs per clutch, which are incubated for about two weeks before hatching. Both parents, but mostly the mother, feed the babies right after hatching. Once the babies grow feathers, the parents are rarely seen together, each one splitting up care for half of the fledglings until they are ready to leave the nest after a month.

Conservation Efforts

These birds migrate in the nighttime, so they are at risk for collisions with reflective buildings, telephone towers, and other man-made structures. Also, parts of their northeastern breeding grounds are threatened by deforestation and habitat loss. 

Help this Species

Be a smart consumer. Choose products made with sustainable ingredients, such as Smithsonian certified Bird Friendly coffees, which support farmers striving to limit their impact on wildlife and habitat.

Practice ecotourism by being an advocate for the environment when you’re on vacation. During your travels, support, visit or volunteer with organizations that protect wildlife. Shop smart too! Avoid buying products made from animals, which could support poaching and the illegal wildlife trade.

Be a responsible cat owner, and keep cats indoors or under restraint when outside. Never release animals that have been kept as pets into the wild.

Support organizations like the Smithsonian’s National Zoo and Conservation Biology Institute that research better ways to protect and care for this animal and other endangered species. Consider donating your time, money or goods.

Conservation starts with you! Join a citizen science project where you can help collect valuable data for scientists. Encourage your friends and family to get involved too.

Plant native flowers in your garden to help feed resident and migrating pollinators. You'll make your lawn beautiful and help wildlife at the same time!

Cite this page:
Smithsonian's National Zoo and Conservation Biology Institute. (n.d.). Black-throated green warbler. Retrieved September 14, 2026, from https://www.nationalzoo.si.edu/index%2Ephp/animals/black-throated-green-warbler

Animal News

Giant panda Qing Bao takes a bite out of the "5" atop her birthday fruitsicle cake. (Skip Brown/Smithsonian)
September 12, 2026

Happy 5th Birthday, Qing Bao ›

To celebrate giant panda Qing Bao's birthday, keepers went "far out" and created a 1970s-themed fête full of bright colors and iconic pop culture slogans.

Sloth hangs upside down
September 11, 2026

See These 5 New Animals at Your Next Visit to the Smithsonian's National Zoo ›

From a spunky new sloth to a dazzling electric eel, get ready to meet the newest residents making themselves at home.

Closeup of a scaly giant tortoise's head
September 08, 2026

Happy 50th 'Zooniversary' to Chyna and Rulon, the Zoo’s Aldabra Giant Tortoises ›

There are plenty of objects and artifacts at the Smithsonian that are old. But at the National Zoo, there's not much older than Rulon and Chyna.

More News