Thursday, October 22, 2009

Favorite Bird

I am sometimes asked what is my favorite bird.  Erika says my favorite bird is the last one I've seen.  I maintain my favorite is the Common Loon.  I love their long dives, their ability to slowly submerge like a submarine, and, of course, their yodels and cries echoing across the northern wilderness.

Tuesday, October 20, 2009

Black-throated Blue Warbler

I banded and released this Black-throated Blue Warbler on 20 October 2009 in Northfield, Rice Co., Minnesota.  One of the joys of banding birds is encountering uncommon species.  This warbler breeds  in Minnesota only in the far northeast and is an uncommon to rare migrant elsewhere in the state.

Monday, October 19, 2009

Hermit Thrushes

I have been banding many Hermit Thrushes this fall.  If you look at fall thrushes, especially Hermit Thrushes, carefully, you will notice that they often have spotted secondary coverts.  These are unmolted juvenile feathers, indicating that you have a bird hatched this calendar year. (Birds without secondary spots are not necessarily adults, however, since the spots eventually wear away.)

Saturday, October 17, 2009

How does one find joy in common birds?

Al Schirmacher of Princeton, MN, asked the MN-listserv, "How does one find joy in common birds?"
Digital photography has revolutionized my birding.  Today I caught only my second crow, which I banded and photographed--a common bird but not so common in the bird net.  This  bird was with about six others drinking at our backyard water feature. (Note the dull alula feather--an indication that this bird was hatched this year.)

Now I am just as likely to chase after a good bird photo as an unusual bird report.  One day in South Dakota I went out in search of displaying Red-winged Blackbirds.  Imagine my surprise when I found this odd Red-wing!
It also proved hard to find a decent House Sparrow photo.  I spent the greater part of a day in search of this photo:

Friday, October 16, 2009

Oystercatcher Eye Flecks

Erika and I came eye-to-eye with a Black Oystercatcher in January 2008 near Morro Bay, California. I was amazed at the odd shape of the bird's pupil. It turns out that the odd shape is caused by black pigment on the oystercatcher's iris. Furthermore, this mark can be used to tell the oystercatcher's sex. For more information see: Secrets in the eyes of Black Oystercatchers: a new sexing technique. Brian M. Guzzetti, Sandra L. Talbot, David F. Tessler, Verena A. Gill and Edward C. Murphy Journal of Field Ornithology Volume 79 Issue 2, Pages 215 - 223 Published Online: 3 Jun 2008.

We came across an American Oystercatcher in September 2009 at Martha's Vineyard. It also has an iris fleck. Note the bands on this bird. We submitted this photo to the Bird Banding Office but have not heard where the bird was banded.

Cedar Waxwing with Tricolored Tail

Erika and I banded 22 Cedar Waxwings all caught at the same time in Northfield today, 13 October 2009. One was interesting: it had a tricolored tail! Its right outer tail feather tip was white. The central feathers where yellow-tipped. the left two outer feathers were orange-tipped.

I have read about orange-tipped waxwing feathers before. See, for example: This paper suggests that the cause of orange-tipped feathers may be from honeysuckle that contains rhodoxanthin. "The ripe red berries of these shrubs are available from June through July. Nestling waxwings, which develop rectrices at this time, may be fed honeysuckle berries and consequently grow orange-tipped tails. Adults do not normally molt rectrices until the berries are no longer available, and nearly always have yellow-tipped tails. Several immature birds with orange tail bands were found growing yellow-tipped replacement tail feathers in September and October, after the honeysuckle fruiting period; two yellow-tipped birds were growing orange-tipped replacement feathers in July, when honeysuckle berries were available."