Thursday, April 26, 2012

Lincoln's Sparrow: the skulker

Lincoln's SparrowLincoln's Sparrow amid purple dead nettles, Forest Grove, Oregon on 13 April 2012 by Greg Gillson

 
If I were to ask what comes to mind when I say "spring migration," I bet it wouldn't be Lincoln's Sparrows. Certainly, colorful neo-tropical migrants such as warblers, orioles, and tanagers, or even the drab green flycatchers, would come to mind first.

Earlier this month I found an unusually high number of Lincoln's Sparrows at the Fernhill Wetlands. It seems that there was a fairly decent migration of these birds overnight. One corner of a cut corn field had a "flock" of a dozen birds in a very small area. I found an equal number elsewhere, scattered around as is more typical.

 
Lincoln's SparrowLincoln's Sparrow on a blackberry cane, Forest Grove, Oregon on 13 April 2012 by Greg Gillson

 
These birds breed in high mountain snow-melt meadows throughout the Pacific Northwest. Some birds winter where water remains open. But numbers of migrant birds move through in spring and fall, hiding in the tall grass--stealth migrants--their retiring ways hiding their actual numbers. It doesn't help that they appear very similar to the abundant resident Song Sparrows and the abundant migrant Savannah Sparrows.

Unlike the Song Sparrows--which are highly interested in investigating anyone venturing near--Lincoln's Sparrows often slip away quietly and hide.
 
Lincoln's SparrowLincoln's Sparrow on a cut corn stalk, Forest Grove, Oregon on 13 April 2012 by Greg Gillson

 
Song Sparrows in the Pacific Northwest are rather dark rusty with longer rounded tails they pump in flight. When they flush, they often land in the tops of shrubs to keep an eye on you. Savannah Sparrows appear more straw yellow, with forked tail. When they fly off they generally go quite a ways to land in grass or on the bare ground. They undulate like goldfinches in flight. Lincoln's Sparrows are shorter tailed and gray-brown. When they take to flight they often pop up in the air nervously before diving for nearby ground cover. All three sparrows occur together in wetland areas. But these color shade, shape, and flight style differences all help separate them with only a brief view.

2 comments:

  1. Do they all have fuzzy heads like this or is that a juvenile?

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    1. These are all adults, Melissa, during their spring migration. Birds can adjust their feathers. For instance, fluffing them up when cold or sleeking them down. Some birds, such as sparrows, have longer feathers on their hind crowns. When they raise them, it forms a partial crest. Birds sometimes raise their crown feathers when alert to danger or displaying to females. It's fairly typical for this species to show a slight crest. See my photo archive: http://www.pbase.com/gregbirder/lincolns_sparrow

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