Spring 2006 Notes and Highlights for May 2 - 14 (cont'd) click here for Season Totals click here for May Totals

• The May showcase of bright bird colors continued with this brilliant adult (ASY) male Baltimore Oriole, one of three banded on 6 May.  More clearly visible in the detail photo of his tail below, this bird was an unusually dark reddish orange (yet another diet-based plumage variation?)

• The next round brought us the second of our three BAOR's for the day.  This time it was an immature (SY) male that provided a great contrast with the adult male tail above.  Its tail had ten retained pale brownish yellow juvenal rectrices (note the much more extensive wear of these compared to the adult rectrices above) and two black "adult" central rectrices grown during its first prealternate molt.

• While the topic of aberrant Hooded Warbler plumages is not new to our website, the discussion usually revolves around adult females showing a nearly complete and very male-like hood (for example, see highlights from July of last year).  This time, however, it was a SY male that caught our attention.  It was the most incomplete hood we have ever witnessed on a male, of any age.  As Jon Dunn and Kimball Garrett quote in the species account for Hooded Warbler in their Peterson Field Guide, first spring males and adult males are indistiguishable in the field.  Given the male-like appearance of this bird's cloaca and its wing length of 65.0mm, we feel confident in our determination that it was a male.  Based on a sample of over 1000 males analyzed for and published in EBBA Monograph No. 1 - Relationships among body mass, age, sex, fat, and wing length for 170 species of birds banded at Powdermill Nature Reserve, this bird's wing length was just about average for immature (HY/SY) males; furthermore, the average wing length for females banded at Powdermill (n = ~1300) is 63.0mm, and no female has measured greater than 65.5mm.

• A preview of coming attractions-- some other interesting/confusing warbler

plumages by sex in the second half of May.

• The morning before our third and final group of participants arrived for the advanced bander development workshop, a pair of Belted Kingfishers dropped into the pockets of our 61mm mesh net which is  strategically positioned on the dike between two of the small ponds at Powdermill.  One proved to be an adult (ASY) male and the other an immature (SY) female.

 

 

With the opportunity for a direct side-by-side comparison, it was fascinating to notice the differences in the color, pattern, and condition of the two birds.  Naturally, the SY female whose spread wing is on the right has much more worn flight feathers (all but some inner secondaries being retained juvenal), while the ASY bird's wing is comparatively very dark and unworn.  When you have two birds in hand that you know represent different age or sex classes, it is interesting to look for other possibly informative plumage criteria for determining age and sex.  For example, we noticed there is much more prominent white spotting on the outer webs of the middle primaries of the ASY bird and the large white spots on the inner vanes of those feathers reach all the way to the feather shaft in the ASY but not the SY bird.  Because the birds differed both in age and sex, we cannot be sure if this wing coloration difference is a possible criterion for age or sex determination.  Of course, it could easily be a case of individual variation that really is not reliable for making either determination.  But, you can be sure that we will take a look at this feature on all of the BEKIs we catch until we have an answer!

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• Our first Pileated Woodpecker for the year certainly got the workshop off to a raucous and rowdy start the very next morning but, without a doubt, it was a great highlight for all.

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• A Swamp Sparrow and Lincoln's Sparrow caught in the same net round provided another great comparison, just this time between two superficially very similar species.  While breeding adult male Swamp Sparrows usually have a bright reddish brown cap and are pretty unmistakable, the bird on the left in the photo below is more likely a female and is quite similar to the Lincoln's Sparrow on the right.  In all plumages, however, Swamp Sparrows have darker more rust colored back streaking and, as shown in the bottom photo, muddy white wash on the breast.  The Lincoln's Sparrow has buffy wash on the breast and sides and is also very finely streaked.  At Powdermill, Swamp Sparrows are a common breeding bird while Lincoln's Sparrow is strictly a migrant with their nearest known breeding grounds in the Adirondack Mountains of New York.

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• Finally, we end this update with our first and only Cerulean Warbler banded for the season, an adult female--possibly one of the most confusing spring warbler plumages there is!

• We want to thank the four participants in our advanced bander workshop held from May 9 - 14 (from left to right): John Rushin (Missouri), Andy Eller (Kentucky), Jack Hilsabeck (Missouri), and Joe Schreiber (far right - Maryland) pose with PARC's Bob Leberman, Bob Mulvihill, Adrienne Leppold (with Kodama, a.k.a. Kody), and Keri Parker (Kody's owner) with Puppy.

• Since this was Kody's first introduction on the website, we felt

he needed another picture that better did him justice.
Here's Kody with his favorite bunch of toys.

Last Updated on 05/30/06
By Adrienne J. Leppold and
Robert S. Mulvihill