Swamp Sparrow - Melospiza georgiana

Swamp Sparrow has a partial preformative molt, and limited prealternate molts that are largely restricted to feathers on the head. Most Swamp Sparrows can be aged by plumage characteristics. Adults can be sexed by both plumage and brood patch / cloacal protuberance during the breeding season, but sex can usually not be determined for Swamp Sparrows in formative or basic plumage.

Juvenile plumage is very similar to that of Song and Lincoln's Sparrows; Swamp Sparrow tends to have particularly short wings and can be identified by the combination of narrow malar stripes and yellowish upper mouth lining.

Quick tips

• Look at the tail - uniformly narrow and pointed rectrices OR contrastingly fresh and broad central rectrices are indicative of FCF/FCA (HY/SY), while uniformly broad and more rounded rectrices are typical of DCB/DCA (AHY/ASY).
• Look for molt limits on the wing - on FCF/FCA (HY/SY birds) there is a contrast between replaced greater coverts and the paler and more worn primary coverts, primaries, and secondaries; on DCB/DCA (AHY/ASY) birds the wing is more uniform with more extensive rusty edging to most feathers, but beware the pseudolimit between the greater coverts and adjacent tracts.
• Examine the crown - in fall, FCF (HY) birds have little to no rufous, while DCB (AHY) birds have a substantial amount of rufous; in spring and summer (alternate plumage - DCA/FCA), males have a crown that is mostly to entirely rufous with limited streaking, while females generally have little to moderate rufous with more extensive streaking, but for those with intermediate patterns, sex should be determined based on the presence of a brood patch or cloacal protuberance.

Species account prepared by McGill Bird Observatory (2016). Last updated by Marcel Gahbauer (Mar 2022)