• Our record setting summer banding results easily transitioned us into what is shaping up to be a fantastic fall migration season at Powdermill.  The first two weeks of September have added 26 new species for our fall totals list and quickly boosted individual numbers for some species into the record setting range.  Ruby-throated Hummingbird (105) and Red-eyed Vireo (110) held the top two spots over the last week.  99 Hooded Warblers were surpassed only by the first big push of Magnolia Warblers the second week of September which netted us 118.

• We want to thank the interns, volunteers, and visitors who contributed so much to the banding efforts over the past two weeks:   Mike Comley, Randi Gerrish, Tom Greg, Annie Lindsay, Trish Miller, Felicity Newell, Bob Nugent, Kelly Perkins, Rosemary Spreha, and Guy Ubaghs. Again, we are signally fortunate to have Professor David Norman as part of the Powdermill banding team for three weeks beginning in late August.  In addition to his help with the day-to day banding effort, we always benefit greatly from David's wise counsel.  He continually reminds us that the conservation implications and applications of banding studies are of paramount importance.  We also were very pleased to be paid a visit by Mary Gustafson, recent acting chief and long-time staff biologist at the Bird Banding Lab.  In the photo below David and Mary take a moment to enjoy one of the 99 Hooded Warblers banded during the two-week period being reported on here.

---

• One of several new species for the season banded this period was a hatching year male American Woodcock.  The very narrow outer three primaries on the woodcock's wing (especially narrow in males) create the twittering wing whistle heard during the male's dramatic crepuscular aerial nuptial displays in early spring.  As in early spring, the shorter photoperiod length in autumn also can trigger half-hearted dawn or dusk flight displays by some of this season's hatching year males.

• We posted pictures recently of HY male and female Canada Warblers, but the adult male banded on August 31 (pictured below) was our first individual of this age/sex class.

• Our first Baltimore Oriole of the fall on September 2, a hatching year male pictured below, gives us a good opportunity to talk some more about our favorite subject--yep, you guessed it, MOLT LIMITS!

 

 

As is the case with so many other birds, and as we've mentioned many times before, there are many times when a bird must be aged correctly before its sex can be correctly determined.  This is because young males and adult females of some species often look outwardly very similar, especially in the fall.  The young male BAOR below replaced all his lesser and median coverts (the feathers on the shoulder, or epaulet, of the wing) and the inner three greater coverts (the row of feathers under the shoulder) producing a clear molt limit between greater coverts 7 and 8 (count from the right).  This is about the usual maximum extent of the first prebasic molt in BAORs.

---

• Caught together in the same net on the same net round on September 5th, were these recently fledged  Swamp and Song sparrows.  In their very similar juvenal plumages, the Swamp Sparrow (left) is identified by the comparatively thinner bill, yellowish gape flanges, and less distinct submalar streak.

---

• Also on the 5th, we caught a species that hasn't been banded at Powdermill in two years: Savannah Sparrow (a hatching year bird).  Only in the first years of the Powdermill banding program, 1961-1965, before some large open fields were converted to a series of small marshy ponds, were SAVSs ever caught in numbers >5.  As the pictures below show, the yellowish lores typical of the species are not always present.

---

• The first Cape May Warblers of the season were banded on September 7th.  Both were hatching year birds (male top photo below; female bottom photo below).  CMWAs of both sexes can be readily identified by the orange feather spot at the hindneck, just behind the auriculars (more obvious in the photo of the female below) and by their tiger-like breast streaking (a trait emphasized in the scientific name of the species, Dendroica tigrina).

---

• The molt limits are very obvious on this hatching year male Scarlet Tanager banded on September 9--its juvenal lesser, median and greater coverts, and, somewhat unusually, S9 and the central pair of rectrices, have been replaced.

• Two days later, we banded this fully molted adult male Scarlet Tanager with scattered orange back and throat feathers included in its otherwise olive-yellow basic plumage.  Undoubtedly, this abnormal fall coloration has a dietary basis, like the sometimes orange tail band color seen on immature Cedar Waxwings.

---

• Astonishing numbers of Hooded Warblers have put us at a new season high for the species.  In 2001, 189 were banded, which we surpassed with 190 banded by the end of the period covered here.  Since then (through 9/15; see next update coming soon!), we have banded 14 more!

.
The photos below show extremes of hood coloration for both age classes of females: hatching year female - top (with an unusually extensive black cap like that ordinarily only seen in older females); adult female - bottom (with an almost completely black cap and throat).  In female HOWAs development (to one degree or another) of a male-like black cap is fairly common.  Development of throat black usually lags behind, though, and we have never observed an adult female with as extensively black a hood and throat as the bird pictured (bottom) below.   If you examine the bottom photos closely, you will see that the black throat is not entirely solid and not very glossy, as it would be in an adult male.  Also, based on our analyses of 2,865 HOWAs in the EBBA Monograph No. 1, the bird's wing length, 64.5mm, was just a little higher than our average for adult females (63.7mm) but well below our average for adult males (67.2mm).

• Finally, in ending page 1 of this update, an intensely black-and-orange adult male American Redstart whose true brilliance really isn't done justice by the photos below.

---

Next Page

< HOME >

Last Updated on 09/13/04
By Adrienne J. Leppold and
Robert S. Mulvihill