Wintering Myrtle Warblers!
Yellow-rumped Warblers are among our most recognizable warblers in the United States. Affectionately, people call them, "Butter Butts," due to the yellow rump patch that all ages/sexes have except juvenal phase Yellow-rumped Warblers. They winter farther north than any other warbler species making their viewability accesable at almost all seasons. They flock up when migrating and wintering into very large groups. We have two groups of Yellow-rumps here in the US and they include "Myrtle," and "Audubon's," warblers. Below I will highlight some of the differences between the two.
Both types of Yellow-rumps act very similarly. They are very active feeders typically in large groups. They will "sally" for their food and hover-glean as well. Hover-gleaning is when you see the bird in question take to the wing, hover underneath the food source, and then pick their fruits off of the tree. They both breed in coniferous forest in their respective ranges, but Audubon's breeds at higher elevations up to treeline. They both will feed at all heights within the tree, but usually tend to feed mid-height or lower.
"Myrtle" Warbler: Breeds in the eastern United States as well as farther north in Canada all the way into Alaska. Breeding birds can be easily told by white throats, bolder face pattern including white supraloral spot, and slight supercilium. Fall/Winter birds are a bit more difficult, but certainly identifiable. Myrtle's will have that same face pattern but not quite as bold. They will also be a bit more streaked below than the Audubon's Warbler in winter.
"Audubon's" Warbler: These cool little birds breed in the inter-mountain west United States and extend their range up through the Cascades of the Pacific Northwest. Unlike these "Myrtle" warblers shown in the photos, the "Audubon's" warbler won't have the light supercilium in any season. The streaking on the breast will be evident but with finer streaks and less of them. Also, you can see in the photos that the Myrtle warblers have a nice white "hook" that curls underneath the dark auriculars. Audubon's warblers do not carry this attribute and I find that feature very helpful in the field. Audubon's warblers are darker than Myrtles in all seasons particularly breeding when the Audubon's has a black patch on the brast and stomach.
Differences do occur within sexes as well as types, but overall the points I've discussed will give you the jump start needed to correctly identify Yellow-rumped Warblers in fall and winter.
These Myrtle Warblers were photographed with a Nikon D300 and a 500mm F4 Nikkor Lens. Good birding and thanks for reading. Visit nikonbirding.com for infomation regarding Nikon equipment. Also, go to Bill Schmoker's website for a great comparitive photo of Audubon's and Myrtle side-by-side!
1 comments:
Thanks Mike, Down here on Jekyll Island, GA our "Myrtle Warblers" are everywhere. I like to think of them as our faithful winter friends. They are in the mud with the sandpipers, climbing the bark of pine trees and places in between. But there are fewer and fewer every year. I wonder if they are wintering further north. Any ideas?
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