The mourning warbler and MacGillivray’s warbler are two similar looking species of warblers found in North America. Both are small, yellow-bellied songbirds with gray hoods. However, there are some key differences between these two species in terms of their appearance, songs, habitat preferences and range which can help birdwatchers identify them. While mourning and MacGillivray’s warblers can be challenging to tell apart, paying attention to certain distinguishing features can help make identification easier.
Appearance
Mourning and MacGillivray’s warblers share a mostly yellow underside and throat, olive backs, gray hoods, white eye rings and pink legs and feet. However, there are subtle differences in plumage and markings:
- Mourning warblers have more distinct black streaking on the breast and flanks. Their throats and bellies appear more washed out and dull yellow.
- MacGillivray’s have crisper, darker yellow underparts without streaking. The yellow eyeline behind the eye is also more pronounced.
- The gray hood of the mourning warbler extends further down the breast while the hood of the MacGillivray’s stops higher at upper breast.
- Male MacGillivray’s tend to have darker gray hoods than mourning warblers. Females of both species have lighter gray hoods.
- Mourning warblers have a small white tail patch which is usually not seen on the MacGillivray’s.
Appearance | Mourning Warbler | MacGillivray’s Warbler |
---|---|---|
Breast and flanks | Black streaking | Clean yellow, no streaks |
Underside color | Dull, washed out yellow | Brighter yellow |
Gray hood extent | Covers upper breast | Stops at upper breast |
Male hood color | Paler gray | Darker gray |
Tail | Small white patch | No white patch |
So in summary, mourning warblers generally appear duller and more heavily streaked while MacGillivray’s have sharper, crisper plumage patterns. Focusing on hood extent, flank streaking and tail patches are some of the best ways to distinguish them.
Song and Calls
The songs and call notes of mourning and MacGillivray’s warblers also sound different:
- Mourning warblers have a quicker, harsher, almost rattling song. Their song is described as “chook-chook-chook-chook-chookchew.”
- MacGillivray’s have a slower, more melodious, bubbly warbling song. Their song sounds like “twee tweedly-deedly-deedly.”
- The call note of the mourning is a sharp, clear “chip” while the MacGillivray’s call is softer and buzzier.
Mourning warbler songs have a faster tempo and harder, more abrupt quality compared to the slower, more musical MacGillivray’s songs. Call notes differ too, with the mourning’s being sharper and crisper. Being familiar with the unique vocalizations of each species is helpful when identification by sight alone is uncertain.
Habitat
Mourning and MacGillivray’s warblers use somewhat different breeding habitats:
- Mourning warblers prefer early successional habitats like forest edges, openings, brushy fields, and shrubby wet areas.
- MacGillivray’s favor thicker woodlands and moist, dense undergrowth in riparian corridors.
- Mournings occur more often in drier, more open shrubby habitat while MacGillivray’s are more strictly tied to wetter, brushier woodlands.
So mourning warblers can occupy more open, early successional areas while MacGillivray’s are more restricted to dense, wetter woodlands and thickets. Focusing on the moisture and density of vegetation can be a helpful habitat clue. Wet, swampy, streamside woods are much more typical for MacGillivray’s.
Range and Distribution
The breeding and migratory ranges of these species also differ:
- Mourning warblers breed across Canada, the Northeastern U.S. and south along the Appalachians.
- MacGillivray’s breed mainly in the Western U.S. and Canada, from Northwest British Columbia to Southwest Saskatchewan.
- Mourning warblers migrate to southeast Arizona, Central America and the Caribbean for winter.
- MacGillivray’s winter primarily in west-central Mexico.
So mournings occupy more easterly breeding grounds while MacGillivray’s are a western species. Their wintering grounds are also completely different, with mournings going southeast and MacGillivray’s southwest. Location within North America can be a helpful clue for identification.
Range | Mourning Warbler | MacGillivray’s Warbler |
---|---|---|
Breeding | Northeast, Appalachians, Canada | Northwest U.S. and Canada |
Wintering | Southeast Arizona, Central America, Caribbean | West Mexico |
Behavioral Differences
Some subtle differences in behavior can also help distinguish these species:
- Mourning warblers are more skulking and tend to stay low in cover. MacGillivray’s often perch more openly.
- Mourning warblers flick their tails more frequently.
- MacGillivray’s can hover briefly when foraging. Mourning warblers don’t hover.
So mournings exhibit more secretive, skulking habits, flicking their tails often from low perches. Meanwhile, MacGillivray’s forage more openly, even hovering briefly to glean insects. These subtle habits can help confirm identification.
Conclusion
In summary, there are several consistent differences to distinguish mourning and MacGillivray’s warblers:
- Mournings have drabber, streakier underparts while MacGillivray’s are crisply yellow.
- Mourning songs are faster and harsher, MacGillivray’s more melodious.
- Mournings favor drier, open habitats while MacGillivray’s need wetter woodlands.
- They occupy different breeding and wintering ranges, mournings being eastern and MacGillivray’s western.
- MacGillivray’s forage more openly, even hovering briefly.
Focusing on plumage patterns, vocalizations, geographic location, habitat preferences and feeding behaviors can all help distinguish between these two challenging warbler species. With keen observation of multiple characteristics, birders can confidently separate mourning and MacGillivray’s warblers.