Dark-Eyed Junco

Junco hyemalis

Description

The Dark-eyed Junco is a medium-sized sparrow with a rounded head, a short pink bill, and a long tail. There is quite a bit of color variation among Juncos from different parts of the country, but in general these birds are dark grey or brown, with white outer tail feathers that are obvious when the bird is in flight.

Size

Dark-eyed Juncos range from 5.25-6 inches (13-15 cm) in length. The wingspan measures between 7 and 10 inches (18-25 cm). Juncos weigh between 0.6 and 1.1 ounces (18-30 g).

Adaptations

• Nestling Juncos have tarsal (foot) bones that develop very quickly, enabling them to run away from predators even though they have not yet learned to fly!

Diet

In the summer, Dark-eyed Juncos eat insects and seeds. In the winter, berries and seeds are the main food items. Juncos also eat the seeds from weed plants. The Junco that lives at Cosley Zoo receives a fruit mix, a processed insectivore (insect-eater) diet, sunflower seeds and mealworms.

Reproduction

Dark-eyed Juncos begin nest-building in April. The female builds a cup-shaped nest on the ground using grasses, moss, or animal hair. The female incubates the clutch of 3 to 5 eggs for 12 or 13 days. Once the chicks have hatched, both parents bring food for them. Chicks leave the nest at 9 to 11 days, but are partially dependent on their parents for about the first three weeks of life. Pairs typically raise 2 or 3 broods per year.

Shelter and Space Needs

Openings and edges of coniferous and mixed woods; in winter, fields, roadsides, parks, suburban gardens.

Life Expectancy

The life expectancy of the Dark-Eyed Junco averages about 3 years. These birds do have the ability to live up to 11 years, but this is rare due to predation.

Importance to Man

Dark-eyed Juncos are popular with bird watchers and are often found at bird feeders in the winter and during migration. Members of this species also aid in the dispersal of seeds and help to control insect populations.

Fun Facts

• The Dark-eyed Junco is one of the most common birds in North America and can be found across the continent, from Alaska to Mexico, and from California to New York. A recent estimate set the Junco's total population at approximately 630 million individuals.
• Dark-eyed Juncos are also called snowbirds because they are often found around bird feeders in the winter.