Western Tanager

The Western Tanager is a dazzling neo-tropical migrant. Clad in brilliant yellow and red, the experience of watching a flock of these stunning birds move through a grove of fresh leaved alders is to feel momentarily transported to some tropical paradise. Its breeding range is broadly distributed west of the 104th meridian and it ranges farther north than any other Tanager breeding up to 60 degrees N. It winters in much of Mexico and Central America.

Adult Male (spring/summer)

Head and chin are red. Breast, belly, flanks and undertail coverts bright yellow. Nape, rump and uppertail coverts are bright yellow. Back is black. Wings are black with two wing bars: upper yellow, lower white. Tail is black.

Adult Female (spring/summer)

Dull yellow head with yellow chin, dull yellow breast and belly. Undertail coverts bright yellow. Nape is dull yellow. Back is gray, rump and uppertail coverts bright yellow. Wings black with two wing bars similar to adult male. Tail is black. Beak is orangish.

Juvenile

Similar to female. Immature male brighter that female.

General:

Strikingly coloured medium size songbird. Length: 16-19cm. Wing: 29-30cm. Weight: 24-36grams.

Behaviour:

The Western Tanager is a foliage gleaner and forages slowly and deliberately though the trees. It also hawks for flying insects in mid-air and will visit feeders for fruit.

Habitat:

Breeds in open coniferous and mixed deciduous-coniferous forests. In migration they can be found in nearly any treed area including urban parks and gardens.

Information:

As one would guess from its vibrant plumage the Western Tanager comes to us from the neo-tropics and returns there diligently each fall. The diet is primarily insects but also includes fruit. Its song resembles a hoarse robin. The red pigment of the Western Tanager’s face is rhodoxanthin, a rare pigment in birds, which is acquired by diet. The nest is a flimsy open cup made of twigs and grasses and lined with finer material. The clutch is 1-5 bluish-green spotted with brown eggs.

Similar species:

Conservation Status:

Listed as Least Concern.

Capture Rates:

Western Tanager preferred habitat is open coniferous or mixed coniferous-deciduous forests. They are therefore not seen in high numbers directly around our banding station except during the periods of May/June and August/September. Capture rates during these periods reflect dispersal to/from breeding areas when fruit and other food is especially plentiful. Tanagers are medium distance migrants, moving south for the winter as seen by our zero capture rates between October and April.

Molt Summary:

PF: HY partial (Jul-Aug); PB: AHY complete (Jul-Aug); PA: SY partial-incomplete (Feb-Apr), ASY limited-partial (Feb-Apr)
Preformative molt includes no to all lesser and med covs and 0-2 inner gr cov, but no terts or rects.
1st PA includes no to some meds covs, 0-10 inner gr covs, often 1-2 terts and occasionally central rects (or more)
Adult PA includes 0-3 inner gr covs, but no terts or rects.

This HY male in September has replaced all lesser, median and 2 inner greater coverts (GC9) indicated with the red arrow. Notice the glossy black, yellowish washed replaced feathers and pale, dull and lightly pigmented retained juvenal feathers.
Some HY birds can be sexed like this HY male with bright yellow rumps and black median coverts with extensive yellowish tips.

This HY male in August is completing its preformative molt having replaced lesser and median coverts and with GC9 in the process of being replaced. Clear molt limits are visible between the replaced median coverts and retained greater coverts with GC9 (red arrow) a growing feather and thus a molt limit in the making!

This HY female in August is also undergoing her preformative molt with GCs 9 & 10 in sheath, another example of molt limits in the making.
Notice the brownish median coverts with relatively thin and whitish/yellow tips versus the extensive yellowish tips of the HY male above. Notice also the narrow, tapered outer primary coverts diagnostic of first year (HY/SY) birds.

This HY in August shows an incomplete preformative molt with lesser and median coverts replaced, inner greater coverts (GCs 4-10), inner secondary (S5) and all 3 tertials (red arrows). Notice the already very worn and tapered retained juvenile outer primary coverts and visible primaries.

This HY male in August is at the very end of its preformative molt with the carpal covert in sheath (red arrow) and lesser, median and inner greater coverts (GCs 8-10) replaced.

This HY male is showing clear molt limits between the replaced lesser and median coverts and innermost greater covert barely visible (red arrow). Notice again the extensive yellow tips to the replaced feathers in males.

This HY female in September has replaced all lesser and median coverts, the molt limit between the median and greater coverts. Notice the lighter brownish coverts and remiges (primaries and secondaries) of females versus the males above and less extensive and duller yellowish tips to the median coverts.

Another HY female in August showing replaced lesser, median and inner greater coverts, the molt limit indicated with the red arrow between the outer retained GC’s and inner replaced GCs.

This SY male in May has replaced a single median covert (blue arrow) and all greater coverts as part of its first prealternate molt in the late winter/early spring. Notice the now very worn first basic lesser and median coverts and narrow and tapered retained juvenal primary coverts.

This SY male in May is showing clear molt limits between retained juvenal feathers and first alternate feathers (blue arrows). Notice here the very bright and extensively tipped median coverts and the contrast between replaced greater coverts and very narrow. tapered and lightly pigmented primary coverts and alula.

The tail of the SY male above shows all of the birds left rectrices (R1-R6) and right rectrices (R1 & R2) replaced in its first prealternate molt. Notice the difference in colour, sheen, gloss, rachis colour and wear between the retained juvenile feathers and replaced first alternate feathers.

This SY female in May had replaced lesser and median coverts as part of her first prealternate molt in the late winter / early spring. Notice the by now worn inner greater coverts and narrow outer primary coverts.

The tail of the SY female above shows all rectrices replaced in the prealternate molt except for the central two (R1). Notice the brownish rachises of the retained central rects versus the blackish rachises of the replaced feathers.

Also, notice the subtle growth bars across the tail feathers. The fact that juvenal feathers are all grown simultaneously and not sequentially as in all subsequent molts has important consequences for ageing birds.

As feathers grow, feather material is synthesized both day and night. However, diurnal and nocturnal metabolic differences result in variation in the pigment deposited during the day versus that deposited at night, and often these differences can be detected in good light, especially on the flight feathers, as growth bars, subtle bars of color crossing a feather perpendicular to the shaft as can be seen here. The dark bars represent the pigment deposited during the day and the light bars the pigment deposited during the night, so each light and dark bar combined represents 24 hours of growth of the feather.

The wing of the this ASY male in April is a good example of what definitive adult plumage, with no discernible molt limits among the coverts or alula, looks like in spring. Notice the uniformly adult coverts and remiges (primaries and secondaries) and extensively yellow tipped medina coverts.

The tail of the same bird is a good example of definitive adult rectrices in spring with broad and truncate outer rectrices with a noticeable corner to the inner web and glossy black rachises.

Tail shape is helpful in ageing many species being tapered and more abraded on retained juvenal feathers in first year birds (HY/SY) and broad and truncate with a corner to the inner web and relatively fresh in adults (AHY/ASY). The outer retrices (R4-R6) generally show the greatest age specific differences.

However, it is important not to use tail shape alone as it is generally not very reliable because of a) individual variation and b) the possibility of accidental loss and replacement (adventitious molt). For this reason and the fact that tail feathers are frequently lost and replaced between normal molts tail feather shape must be used with great caution by banders, and only with other supporting characters (e.g., molt limits), when determining the ages of birds in hand.