March 2011

Identifying subspecies by behavior – Savannah Sparrow

Identifying subspecies adds richness to your birding by adding another layer of understanding. What’s more, during spring migration, behavior can offer a quick and fairly reliable clue to use when distinguishing local breeders from migrants. This is simply an extension of a bit of advice often given for identifying shorebirds: to watch for birds around

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Distinguishing Green-winged and Common Teal

The Green-winged Teal (known as Common Teal in English-speaking parts of Eurasia) is currently considered a single species by the AOU, but two subspecies are distinctive in adult male plumage and are split into two species by many authorities. Green-winged Teal (American) – Anas crecca carolinensis Common Teal (Eurasian) – Anas crecca crecca ((Common Teal nests in

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Distribution of Greater White-fronted Goose subspecies

The Greater White-fronted Goose (Anser albifrons) occurs throughout much of North America, but is found in largely disjunct populations. Only two North American subspecies are listed by Ely and Dzubin (1994), four by Pyle (2008), but five well-defined “population units” have occurred in North America, and there may be more. Banks (2011) recognizes four of

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Distinguishing the subspecies of Purple Finch

Summary The two subspecies of Purple Finch are fairly distinctive with well-defined ranges. They are best distinguished by overall impression of color and pattern, and more objectively by details of back and head pattern. Virtually all individuals should be safely identifiable in the field, but the frequency and extent of intergradation is unknown. Eastern Purple

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Can subspecies of Mountain Chickadee be identified in the field?

Not really. Only under ideal conditions and with reference to location. Mountain Chickadee is found throughout much of the montane coniferous forest of the west, and up to seven subspecies have been described and named. These were sorted by Behle (1956) into Rocky Mountain, Great Basin, and California groups which differ in a complex mosaic

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