Bird of the Month: American Redstart
Written by Andy McCormick
Andy McCormick, Volunteer and Former Board President of Eastside Audubon
In perpetual motion flashing wings and tail the American Redstart is a joyous bird. Males are black with orange patches on wings and tail, and females are gray with yellow patches.
American Redstart
Scientific Name: Setophaga ruticilla
Length: 5.25”
Wingspan: 7.75”
Weight: 0.29 oz (8.3 g)
AOU Alpha Code: AMRE
AERIAL DISPLAYS ARE SPECIALTY
American Redstarts are very active birds and can be seen using a variety of aerial displays during which they flash their colors. They often forage for insects by sallying out from a branch to catch flies, moths, and midges in a manner very similar to flycatchers. On occasion they also employ hover-gleaning as a Golden-crowned Kinglet would and pick beetles and caterpillars from the underside of leaves while hovering below it.
They also use circling and gliding displays in defense of their nest. A redstart will respond aggressively to an intruder near the nest by circling out on stiff wings toward it. After closing in on the other redstart, it will circle back to its nest. The second redstart will then initiate a ritual circling out toward the first bird and the two may alternate these flights for a few minutes. At other times, a redstart will glide while displaying its wings and tail to mark its territorial border (Sherry, et al).
You can see photos of American Redstarts showing the wings and tail in various displays at the Macaulay Library photo, and videos showing how actively these birds can forage at Macaulay Library video.
NESTS IN WILLOWS AND ALDERS
Fairly common in the northeast corner of Washington, the American Redstart is seen only in localized areas in Western Washington. It is a common breeding bird throughout much of Canada and in the eastern United States.
In the Pacific Northwest, the American Redstart prefers second growth woods especially willow and alder thickets in wet areas, where the female builds an open cup nest close to the trunk or in a fork of a tree. The nest is constructed of grasses and plant fibers and decorated with lichen or birch bark, then lined with feathers. Sometimes old nests of other birds are used (Kaufman).
Typically, four, but sometimes two to five, off-white eggs are deposited. Incubation by only the female lasts less than two weeks, and the young leave the nest at nine days old. Females produce one brood per season, but males can sometimes support two or three females in separate nests (Kaufman).
RESEARCH IN BREEDING AND OVERWINTERING AREAS
The population of American Redstarts remains strong, but there have been declines in certain areas of the Midwest and Southern United States. One threat to them is parasitization by Brown-headed Cowbirds.
Very good studies have linked breeding success of American Redstarts to the quality of their overwintering habitat in the Caribbean Islands. Researchers have found that redstarts which winter in moist habitats such as black mangroves are more successful breeders in North America than those which winter in drier habitats such as thorn forests (Sherry et al). This finding implies that gradual drying of habitats due to climate change could be a threat to American Redstarts in the future.
The American Redstart is in the genus Setophaga, moth eater, from the Greek, setos, moth, and phagein, eating. The genus reflects its flycatching style of foraging. The species name ruticilla, from the Latin rutilus, a warm and glowing red, is a reference to the male redstart’s red-orange flashes in its wings and tail (Holloway).
Photo credit Doug Greenberg.
References available upon request from amccormick@eastsideaudubon.org.