Juncos are small, sparrow-like birds in the genus Junco that are commonly found across North America. There are several different subspecies of juncos, with some key physical differences between them. Two of the most common juncos are the gray-headed junco and the red-backed junco. While they may look similar at first glance, there are some notable differences in their appearance and behaviors.
In this article, we’ll take a closer look at gray-headed juncos and red-backed juncos, exploring their key identification features, geographic ranges, habitat preferences, mating and nesting behaviors, vocalizations, and more. Understanding the differences between these two junco subspecies can help bird watchers properly identify and appreciate them in the field.
Key Identification Features
When observing juncos in the field, the first features to look for are the coloration on the head, back, and sides:
Gray-headed Junco
As the name suggests, the gray-headed junco has a primarily gray head. The back and sides are a brownish gray. The breast is pale gray transitioning into a bright white belly. It has pinkish-brown legs.
Some key identification features of the gray-headed junco include:
– Gray hood extending from the face to the nape and throat
– Pinkish-brown bill
– Brownish-gray back and sides
– Pale gray breast
– Bright white belly
– Pinkish-brown legs
Red-backed Junco
Distinctively, the red-backed junco has a reddish-brown back and hood. The breast is gray and the belly is white. It has pinkish-brown legs like the gray-headed junco.
Some key identification features of the red-backed junco include:
– Reddish-brown hood extending from the face to the nape and throat
– Pink bill
– Reddish-brown back
– Gray breast
– White belly
– Pinkish-brown legs
The hood coloration is the quickest way to distinguish these two junco subspecies. But the back coloration also differs, with gray-headed juncos having a brownish-gray back and red-backed juncos having a distinctive reddish-brown back. taking note of these key features makes identifying gray-headed and red-backed juncos straightforward.
Geographic Range
Gray-headed and red-backed juncos occupy different geographic breeding ranges across North America:
Gray-headed Junco
Gray-headed juncos breed predominantly in mountainous areas of the western United States, including:
– The Cascade Range of Washington, Oregon, and California
– The Sierra Nevada of California
– Rocky Mountains of Idaho, Montana, Wyoming, Colorado, and New Mexico
– Various ranges in Nevada, Utah, and Arizona
They primarily reside in these mountain coniferous forest habitats year-round, migrating altitudinally within their breeding ranges to lower elevations in winter.
Red-backed Junco
Red-backed juncos breed in Alaska, western Canada, and the Pacific Northwest. Their breeding range centers around:
– Alaska
– Yukon Territory
– British Columbia
– Alberta
– Northwest Territories
– Washington
– Oregon
Some populations of red-backed juncos migrate south in winter to the western and midwestern United States. Others remain year-round in northwest coastal regions.
The breeding ranges of these two junco subspecies overlap to some extent in the Pacific Northwest. But gray-headed juncos predominately occur further inland and at higher elevations. Knowing these core geographic ranges aids identification.
Habitat Preferences
Gray-headed and red-backed juncos utilize slightly different breeding habitat types:
Gray-headed Junco
Gray-headed juncos inhabit coniferous and mixed wood forests in mountainous areas. Some typical breeding habitats include:
– Spruce-fir forests
– Lodgepole pine woodlands
– Mixed conifer forests with firs, pines, and aspens
– Open wooded areas with shrubs and thickets
They are found at elevations between 6,500-11,500 feet during the breeding season. In winter, they descend to lower elevations down to 3,500 feet.
Red-backed Junco
Red-backed juncos breed in a variety of forest types, including:
– Coastal coniferous forests dominated by Sitka spruce and western hemlock
– Inland coniferous forests of pines, firs, and spruces
– Deciduous aspen groves
– Forest clearings and edges
They occur at elevations up to about 6,500 feet near treeline. In winter, they frequent both forested and semi-open environments.
While both subspecies inhabit conifer-dominated forests, gray-headed juncos are more restricted to higher elevation mature conifer stands. Red-backed juncos occupy more diverse forest types across a wider elevation range.
Mating and Nesting
Gray-headed and red-backed juncos exhibit slightly different mating and nesting behaviors:
Gray-headed Junco
– Breeding season is late May through July
– Males frequently sing short tunes and call to attract females
– Nest is an open cup built on the ground or low in trees/shrubs, constructed from grasses and twigs
– Clutch size is typically 3-5 eggs
– Incubation period is 11-13 days; only female incubates
– Chicks are fed and cared for by both parents and fledge from nest in about 10-13 days
Red-backed Junco
– Breeding season is mid-April through July
– Males sing from exposed perches to mark territory and attract females
– Nest is an open cup placed in a concealed location on or near ground, made from grasses and moss
– Clutch size is often 4-5 eggs
– Incubation lasts 12-14 days by female only
– Both parents feed chicks; young fledge from nest at 11-15 days
While quite similar, gray-headed juncos start breeding a bit later and have slightly smaller clutch sizes on average. Nest placement also differs somewhat between the subspecies. But overall they exhibit typical open-cup nesting junco behaviors.
Vocalizations
The songs and calls of these two juncos have some distinct differences:
Gray-headed Junco
– Song is a melodic, complex, warbling trill lasting 2-3 seconds similar to a House Wren
– Call is a very high-pitched, almost insect-like “tink”
– Alarm call is a fast “tickytitit”
Red-backed Junco
– Song is a sweeter, slower, buzzier trill than gray-headed lasting 1-2 seconds
– Call note is lower-pitched “chip”
– Alarm call is a rattled “chit chit chit”
The gray-headed junco’s song and call notes are higher-pitched and faster compared to the red-backed junco. These vocalization differences can aid identification when birds are heard but not seen well.
Behavioral Differences
Some other behavioral differences help distinguish these two junco subspecies:
Gray-headed Junco
– Tends to forage in flocks, sometimes mixing with other species
– Males can be aggressive and maintain distinct, small territories
– Very active forager, covering ground rapidly while hopping along
– Readily visits bird feeders and inhabits developed areas
Red-backed Junco
– Usually forages in small, loose groups of juncos
– Males less aggressive about territories compared to gray-headed
– Forages more methodically, deliberately checking substrates
– Warier of humans and less likely to visit feeders frequently
Gray-headed juncos exhibit some feisty, busy behaviors compared to red-backed juncos. Their aggression and affinity for feeders make them more conspicuous in some areas.
Conclusion
While gray-headed and red-backed juncos may seem identical at first glance, a closer look reveals several key differences:
– Gray-headed juncos have gray heads, reddish-brown backs, breed in mountain forests, and have a fast, high-pitched trilled song.
– Red-backed juncos have reddish-brown heads, gray backs, breed in coastal and inland forests, and have a slower, buzzy trill for a song.
Remembering field marks like the hood and back coloration along with habitat preferences, vocalizations, and behaviors enables confident identification of these two very common, but distinct juncos. Paying attention to the details is rewarding and helps bird enthusiasts appreciate the diversity found even among closely related songbird species like these juncos.