Dark-Eyed Junco

Introduction

For this week’s post I thought I would write about a common winter visitor to my backyard the dark-eyed junco.
                                                                                                    Photo Credit Kevin Tomas

Dark-eyed Juncos in my backyard.

The dark-eyed junco is a very common visitor to my backyard during the winter months. During these months I often see dark-eyed juncos daily. Most of the time there are several juncos at the bird feeder, eating the seeds that other birds have dropped. Another common sight is juncos hopping around the yard.  I always enjoy seeing these little grey and white birds hopping around the yard.

During the spring and summer months, I hardly ever see juncos. They begin appearing about mid-November and disappear around mid-March.
  

Dark-eyed Junco Fast Facts  

• The dark-eyed junco is known as the snowbirds for most of the United States. They appear in many areas when winter begins and return to the cold Northeast in spring. “I happen to live in an area that juncos remain in year round.”

• A Junco spends an average of 4 hour a day foraging in summer months and 6 hours a day foraging in winter months.

• Winter flocks of dark-eyed juncos have a home range between 10 and 12 acres.

• Juncos that remain in an area year round have shorter wings then juncos that migrant.

• The oldest know living dark-eyed junco was 11 years old.

• There are seven sub-species of juncos throughout the world.

• Only male dark-eyed juncos sing.

• When searching for food dark-eyed juncos normally hop along the ground rather the walk.

• Juncos help the ecosystem by dispersing seeds and controlling insect populations.

Identification

An adult dark-eyed junco can be identified by its grey head, body, and white stomach. A juncos' bill is a pale pink color. The coloring on a male junco is darker then the markings found on female juncos. The average size of a junco is 5 to 7 inches long with a wingspan between 7 and 10 inches.The average weight of a junco is 1.1 oz.

Diet

The dark-eyed junco will eat a wide range of seeds. In fact around 75% of the juncos diet comes from seeds. Some seeds eaten by juncos include sorrel, chickweed, buckwheat, and seeds found at bird feeders. Juncos will also eat fruit which include elder, raspberries, and blueberries. In addition to this, the junco will feed on many different species of arthropods like beetles, spiders, ants, and flies.

Habitat

Dark-eyed juncos are often located in woodland edges of coniferous and deciduous forests. Coniferous forests have trees like fir, spruce, and pine, while deciduous forests have trees like maple, oak, cottonwood, and aspen. In the winter dark-eyed juncos can be found in a wider range of habitats which include gardens, fields, and woodland. “This is why I only see dark-eyed juncos in the winter because my yard is a mix of fields, grassland, and woodlands.”

 

Male (left) and Female (right) Juncos. Photo Credit SriMesh

Predators

Juncos normally live in open areas which means they can easily be attacked by predators like hawks, owls, cats, and shrikes. Mammals like weasels, martens, and even chipmunks and squirrels may eat young juncos or pray on junco eggs.

When a predator is spotted, adult birds will flee to safety. If a nest is threaten, the parents will chirp loudly and fly around the nest. In some situations juncos will dive at the predator attacking the nest.  

Nesting and Eggs 

Junco nests are built in different locations, which means nests can be very different from one another. Normally, nests are built in areas like rock faces, under buildings, sloping ground, or the roots of an upturned tree. A nest built on the ground may be nothing more than a lining of pine needles and grass. Other nests may be built from leaves, moss, and twigs, then lined with moss, grass, and ferns. The nest building process normally takes 3 to 7 days to complete. The female junco will uses her body to form the shape of the nest.

Breeding season for dark-eyed juncos begins in April. A female lays 3 to 5 eggs. Junco eggs are normally white with brown markings, however, eggs can also be gray or pale green with gray or green markings. The female incubates the eggs for 11 to 13 days. When the eggs hatch, both parents help with feeding duties. The young juncos will leave the nest 9 to 13 days after hatching. Juvenile juncos are pale and could even be misidentified as sparrows. Young juncos gain adult plumage after 2 to 3 months.

 

Photo Credit S. Kropidlowski

Dark-eyed Junco Flocks

The dark-eyed junco is a social bird during winter and autumn months. During these months small flocks of 15 to 25 birds are formed. Flocks form up during the morning hours and disperse in the evening hours to roost for the night. The flocks have a social hierarchy males birds are dominant over young and female birds. The male birds spend the winter in northern areas, mainly to be closer to the breeding grounds and to claim territories.
      Female juncos do not need to compete for territories. So, they spend the winter further south. This allows them to get more food, and not have to compete with male juncos.
      It is also common for flocks of Juncos to be associated with American tree sparrows. If you have ever watched juncos in the winter you probably noticed tree sparrows often feed in the same areas as the junco flock.  

Conclusion

In my backyard the spotting of a dark-eyed junco is always a reminder that winter is coming. Juncos may not be the most beautiful or rare creature I have seen in my back yard, but they are always a welcome sight. Winter would not feel the same without a few dark-eyed juncos hopping around the yard. Join me next time as we explore wildlife in my backyard and other nature topics.  

References and Additional Resources 

Cornell University. (2015). Dark-eyed Junco. Retrieved from

https://www.allaboutbirds.org/guide/Dark-eyed_Junco/lifehistory

National Audubon Society. (n.d.). Dark-eyed Junco. Retrieved from

http://www.audubon.org/field-guide/bird/dark-eyed-junco

Penn State New Kensington. (2002). Northern Junco. Retrieved from http://www.psu.edu/dept/nkbiology/naturetrail/speciespages/northern_junco.html

University of Michigan. (2014). Junco hyemalisdark-eyed junco. Retrieved from http://animaldiversity.org/accounts/Junco_hyemalis/#predation

 Photo Credit and References

Ken Thomas KenThomas.us(personal website of photographer), Public Domain, https://commons.wikimedia.org/w/index.php?curid=1828186

 S. Kropidlowski, Kanuti National Wildlife Refuge (USFWS) - http://images.fws.gov/default.cfm?fuseaction=records.display&CFID=3846274&CFTOKEN=86002964&id=817B6BF5-C282-F93F-C43297208080BF75, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4657055

SriMesh - Own work, CC BY-SA 3.0,

https://commons.wikimedia.org/w/index.php?curid=8049851

SriMesh - Own work, CC BY-SA 3.0,

https://commons.wikimedia.org/w/index.php?curid=8049927