Yellow-rumped Warblers are small songbirds that breed in northern North America and migrate south for the winter. They are one of the few warbler species that you can find in much of North America year-round. Yellow-rumped Warblers are known for their bright yellow rumps, but their plumage changes throughout the year. So what color are they in the fall?
Quick Answer
In the fall, Yellow-rumped Warblers transition from their bright breeding plumage to their more muted non-breeding plumage. The males retain some bright yellow on their face, throat, breast, sides, and rumps. Their backs are brown and streaked. Females and immatures are dull gray-brown on the head, back, and chest with indistinct streaking and just a hint of yellow on the face and rump.
Yellow-rumped Warbler Overview
The Yellow-rumped Warbler (Setophaga coronata) is a small songbird that measures 4.7-5.5 inches in length and weighs 0.3-0.4 ounces. They have a wingspan of 7.5-9.1 inches. Their breeding habitat is coniferous and mixed forests in Canada and the northern United States. Some populations migrate south through the United States and Central America to winter in Mexico and the West Indies. Other populations may be permanent residents or short-distance migrants in the southern parts of their breeding range in the United States.
Taxonomy
Yellow-rumped Warblers belong to the family Parulidae (wood-warblers) and the genus Setophaga. There are four recognized subspecies:
- S. c. coronata – breeds from eastern North America to the Rocky Mountains
- S. c. auduboni – breeds in western North America
- S. c. nigrifrons – found in Guatemala and El Salvador
- S. c. goldmani – resides in southern Mexico
Identification
Yellow-rumped Warblers can be identified by the following characteristics:
- Yellow patch on the rump, upper back, throat, and sides of the neck (males)
- White or gray underside with dark streaking
- Brown or gray back with black streaks
- Black eyeline and sideburns
- Yellow or white wingbars
- Dark legs and beak
Fall Plumage Differences
In the spring and summer breeding season, male Yellow-rumped Warblers have bright, colorful plumage. Their upperparts are blue-gray with bold black streaks. The face, throat, breast, sides, and rump patches are vibrant yellow. Females have paler gray-brown upperparts and duller yellow patches.
In the fall and winter months, their plumage is much more subdued. The males transition to mostly gray and brown upperparts with some remnants of yellow on the face, throat, breast, sides, and rumps. Their wingbars remain white. Females and immatures are even more nondescript with little to no yellow patches remaining.
Why Do Yellow-rumped Warblers Molt into Fall Plumage?
Yellow-rumped Warblers molt into their dull fall and winter plumage for a couple of reasons:
- Camouflage – their muted colors help them blend into the autumn woodlands and forests as the leaves change.
- Energy conservation – duller feathers take less energy to produce than bright colorful ones.
By molting into camouflaged non-breeding plumage, they can conserve energy as food becomes more scarce while still blending in with their surroundings.
Differences Between Males, Females, and Immatures
The differences between male, female, and immature Yellow-rumped Warblers are most apparent in the fall and winter plumage. In breeding plumage, males have much brighter yellow patches while females are duller. But in the fall, the differences are more striking:
- Adult males – Gray to olive upperparts with some black streaking. Yellow patches on throat, face, sides, and rumps. Black sideburns and eyeline.
- Adult females – Plain grayish-brown upperparts. Little to no yellow patches. Faint streaking.
- Immatures – Dull brown upperparts. No yellow patches. Buffy underside with faint streaking.
Range and Habitat
Yellow-rumped Warblers breed across Canada and the northern United States including:
- Alaska
- Canada
- Northern Pacific Northwest
- Midwestern states
- Northeastern states
- Appalachian Mountains
They reside in coniferous and mixed forests and woodlands as well as parks and gardens during breeding season. Some key details about their breeding habitat:
- Nest in conifers like pine, spruce, and fir trees
- Found at high elevations in western mountains
- Prefer young forests with dense understory
- Also nest in mixed forests, parks, and suburban areas
In the fall and winter, most Yellow-rumped Warblers migrate south to the southern US, Mexico, Central America, and the Caribbean. Their winter habitat includes:
- Southern pine and pine-oak forests
- Tropical forests
- Forest edges
- Parks and gardens
- Coastal areas
Some Yellow-rumped Warblers, particularly in coastal areas, are permanent residents throughout their range.
Behavior
Yellow-rumped Warblers display some key behaviors during the fall and winter months:
- Foraging – Forage by gleaning insects and berries from trees often by hovering. Favor bayberry and wax myrtle berries in winter.
- Migration – Most populations migrate south beginning in August, with peak migration in October and November.
- Social – Travel together in flocks during migration and winter months.
- Vocalizations – High, squeaky “tsee” call year-round. Softer warbling song in winter months.
Diet
Yellow-rumped Warblers are omnivores and their diet varies throughout the year. In the fall and winter they eat:
- Insects – beetles, flies, moths, caterpillars
- Spiders
- Berries – bayberry, wax myrtle, pokeweed, sumac, Virginia creeper
- Fruit – magnolia, holly, dogwood
- Nectar from flowers
- Tree sap
Their ability to eat berries and wax myrtles sets them apart from other warblers. This allows them to winter farther north than most other warblers.
Conclusion
In summary, Yellow-rumped Warblers transition from bright yellow-patched breeding plumage to more nondescript fall and winter plumage. Males retain some yellow patches on the face, sides, and rump while females and immatures are very dull gray-brown. Their muted fall plumage provides camouflage and conserves energy during migration and winter when food is scarce. Their diverse diet, including berries, allows them to overwinter farther north than many other warbler species.