The blue grey gnatcatcher is a small songbird that is found throughout much of North America. Identifying this bird by sight can be tricky, as they have similar coloration and size to many other birds. However, with some tips on field marks, songs, behavior, habitat, and range, an observer can confidently identify a blue grey gnatcatcher.
Field Marks
The blue grey gnatcatcher has predominantly blue-grey plumage on its upperparts and head, with a white underside. The most distinguishing field marks of this species include:
- Long black tail with white outer tail feathers – This is the most prominent identifying feature of the blue grey gnatcatcher. The black tail is very long for the bird’s small size.
- White eye ring – A bold white eye ring surrounds its dark eye.
- Thin bill – The bill is very slender and all black.
- White wing bars – Two faint white wing bars are visible when the wings are outstretched.
- Blue-grey coloration – The head and upperparts are a distinctive blue-grey color. The undertail coverts are also blue-grey.
- Sexual dimorphism – Males have black feathers on their crown, which females lack.
In flight, the long tail and white outer tail feathers are the most helpful identification marker. Perched birds can be identified by the combination of blue-grey upperparts, bold white eye ring, long black tail, and slender all black bill.
Song
The song of the blue grey gnatcatcher is a very high-pitched, wheezy series of notes. It is often described as sounding like a squeaky toy. They have a variety of different call notes including a loud “zreeep” alarm call. Their songs and calls are very high frequency and piercing to the human ear. Learning the unique vocalizations of this species can help identify them by ear.
Behavior
Blue grey gnatcatchers are very active birds, constantly moving as they forage for insects in trees and shrubs. Some key aspects of their behavior include:
- Constantly flicking tail – They characteristically flick their long tail as they move through branches.
- Frequent hovering – They will hover briefly to glean insects from leaves and branches.
- Forages high in trees – Tends to forage high up in the canopy of trees.
- Joins mixed flocks – Often joins mixed flocks with chickadees, nuthatches, warblers etc.
- Does not visit feeders – Unlike some other songbirds, they do not frequent bird feeders.
Their habits of flicking the tail, hovering, and foraging high in trees help set them apart from other species.
Habitat
Blue grey gnatcatchers occupy a variety of wooded habitats across North America. Typical habitats include:
- Deciduous forests
- Pine forests
- Riparian woodlands
- Open woodlands
- Scrublands
- Suburban parks and yards with trees
They are found anywhere there are trees and shrubs where they can forage for insects. They do not occupy dense, closed canopy forests as much as open, edge habitats. In western regions, they are often found in scrubby pinyon-juniper woodlands.
Range
The blue grey gnatcatcher has an extensive range across the United States, Mexico, and Central America. In the U.S. and southern Canada they are found coast-to-coast across the southern regions. Their range extends northward in the interior western regions to southern British Columbia, Alberta, Saskatchewan, and west-central Manitoba.
On the east coast, their range extends northward to southern Ontario, central Quebec, New Brunswick, and Nova Scotia. They are migratory over the northern parts of their range, wintering in the southern U.S., Mexico, and Central America.
Similar Species
The blue grey gnatcatcher could potentially be confused with a few other species that occupy similar habitats. However, with good views and attention to detail, they can be confidently identified by an observer who is familiar with them.
Blue-gray Gnatcatcher vs. Ruby-crowned Kinglet
The ruby-crowned kinglet often shares habitat with the blue grey gnatcatcher. However, the kinglet lacks the long, black tail that distinguishes the gnatcatcher. The kinglet is also more olive-green above and has a bold white eye ring. The gnatcatcher is blue-grey above with a thinner, faint eye ring.
Blue-gray Gnatcatcher vs. Black-tailed Gnatcatcher
In the Southwest U.S., the black-tailed gnatcatcher replaces the blue-gray gnatcatcher in some areas. It is very similar in appearance, but the entire tail is black right to the base rather than having white outer tail feathers.
Blue-gray Gnatcatcher vs. Eastern Bluebird
The male eastern bluebird has similar blue upperparts to the blue-grey gnatcatcher. However, bluebirds have a stockier build, thicker bill, lack the long tail, and have an orange-reddish breast.
Key Identification Tips
Here are some key tips to confidently identify a blue grey gnatcatcher in the field:
- Long, black tail with bold white outer tail feathers
- Blue-grey upperparts
- Thin, all black bill
- Constantly flicking tail
- Light, squeaky vocalizations
- Forages high in trees
Conclusion
Identifying the blue grey gnatcatcher is straightforward once an observer is familiar with this species. The combination of its long black and white tail, blue-grey upperparts, vocalizations, and active foraging behavior make it distinguishable from other similar birds. Paying attention to details like the tail pattern, bill shape, eye ring, wing bars, and habits will help any birder reliably pick out this species. With practice, the unique blue grey gnatcatcher can be identified by sight, sound, behavior, and habitat.
