• Tuesday, August 3 - Sunday, August 15:  After a busy couple summer months, the first official banding weeks for our fall season seemed to be slow, but, actually, were normal for the beginning of August as compared to totals from recent years past.  As expected, our captures continued to reflect the shift to greater numbers of fall migrants.  On August 5th, we captured this hatching year Spotted Sandpiper of unknown sex.  Juveniles are identified by their boldly barred brown and buffy inner median coverts along with the overall very unworn appearance of the plumage.

• Also on the morning of the 5th, we caught what was most likely one of our last Louisiana Waterthrushes, apart from possibly recapturing our very late molting adult featured on the website last month.  In the same net round, we caught what was only the second Northern Waterthrush fall migrant for this year.  At Powdermill, Louisiana  Waterthrush (LOWA) and Northern Waterthrush (NOWA) migration overlaps only by a couple of weeks; most LOWA's are well on their way south even before the first NOWAs begin moving through in any numbers.  The photograph below is of the LOWA (left) and NOWA (right), both hatch year birds.  The LOWA is the bigger of the two waterthrushes, has a heavier bill and has less buffy in the eyeline, the latter not always a reliable distinguishing mark as NOWAs can sometimes be near white and some LOWAs may have a buffier tinge to the feathers.  Even more characteristic between the two is the difference in the leg color.  LOWA's are easily identified by their "bubble gum" pink legs.  In addition, a plumage difference between waterthrushes probably most often overlooked is the undertail coverts.  NOWA's have fine gray/brown streaking in the center of the long undertail covert feathers, which if present at all in LOWAs, (the bird banded this week had none), would be much more reduced and limited to only a few central feathers.

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• As the season progresses, we expect the peak of our Ruby-throated Hummingbird catches to synchronize with the peak flowering of three of their favorite, and very abundant, food sources near the banding  headquarters, Cardinal Flower Lobelia cardinalis (left), Spotted Touch-me-not or Jewelweed Impatiens capensis (top middle), and Trumpet Vine Campsis radicans (bottom right), pictured below.  With a 43 year average of 78 birds in the months of July and August and some of the flowers beginning to develop seeds, we were beginning to wonder if this was going to be a low catch year for us, but just in the first two weeks of August we have added 52 new birds, already pushing us over the average for the entire months of July and August combined, by three birds.

• Of all North American birds that visit flowers, none other than the hummingbird is more well known for its nectar loving and pollinating relationship with the plant world.  In this symbiotic relationship, hummingbirds are attracted to the sweet, energy rich nectar many of these plants produce.  As they feed, tiny pollen grains produced by the stamens (the male part of a flower) stick to the hummingbird's head and are then carried on the feathers to other flowers the bird feeds on where the grains brush off onto the pistils (the female part of a flower containing the ovary), thus achieving cross-pollination.  The photo below is of a hatch year female banded this week.  This picture speaks for itself about the contribution and importance of hummingbirds to the pollination process.

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• We have discussed before the high plumage variability within species of many birds.  In young male Hooded Warblers, the "hood" typically looks entirely black, like an adult male, although closer inspection will show varying amounts of thin olive tipping on the black head feathers.  The hatch year male Hooded Warbler banded this week (photo below) showcases this variation because of the unusually extensive olive green veiling on its hood.   This case re-emphasizes the importance of correctly ageing birds before sexing them in the hand because this plumage resembles what might be seen in the case of some adult females of the species.

• On Wednesday, August 11th, we finally netted the Green Heron which had been seen flying around the banding headquarters much of that week.  It was a hatch year female, aged by overall plumage appearance and the presence of a couple juvenal feather tufts remaining on the top of her head (barely visible in the photo below) and sexed female by the chestnut streaking in the crown and on the sides of the head and neck (according to the description in Bent's Life Histories of North American Birds, 1963).  The photo below was taken in attempts to show the powder down feathers which outline the furcular hollow and are unique to herons and bitterns (the yellow feathers near the bottom of the photo that form a "V").  While most other birds' feathers produce a small amount of powder, powder feathers are highly developed in this family and the quill of the powder down is continuously growing and disintegrating, thus creating the powdery substance.  Aptly named, the powdery particles produced by these down feathers function, in the herons and bitterns, for preening, to help remove fish slime and oil from the feathers.

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• New for the year was this very motley looking adult female Blue-headed Vireo banded on August 15th.  Just beginning her prebasic molt, she had dropped her first few (inner) primaries (the long flight feathers which fold across the birds back), a couple inner greater coverts (the second row down from the shoulder of wing feathers), and some body feathers, particularly around the head.

• Also banded on the 15th was this second year male Northern Cardinal undergoing prebasic molt with its definitive adult plumage coming in very scarlet rather than red/orange.  The belly feathers and wing coverts in particular are quite striking (the former being vivid scarlet and the latter a dark plum red).  Notably on this bird, three feather generations are visible.  The extent of the prebasic molt in cardinals is variable from none to (in <25% of NOCAs at POwdermill) all flight feathers.  The bottom photo shows these three generations: juvenal feathers (primary coverts - the very washed out gray/brown worn feathers in the middle of the photo - and scattered body feathers), 1st basic feathers (scattered worn orange body feathers visible at the far right of the picture), and 2nd basic/adult feathers molting in (the bright scarlet and dark red flight and body feathers).  Of course, as you can see, the banders at Powdermill spare no expense or sacrifice for getting great pictures of our birds to share on the website.

• Continuing with photo highlights from the 15th is this hatching year Least Flycatcher.  In taking this bird's picture, we took advantage of the tendency for Empidonax flycatchers to "play dead."  We intentionally used the flat-on-its-back pose for this bird because we were trying to show its yellowish underparts.

• The next photo is of a hatching year Acadian Flycatcher in full juvenal plumage banded earlier in the month.  Noticing a few qualitative features can quickly and easily narrow down "tricky empids"  to species.  For example, compare the leg color between the Least (top photo) and Acadian (bottom photo) Flycatchers.  Least (and also "Traill's," i.e., Willow and Alder) Flycatchers have blackish legs and gray/olive brown back plumage, while Acadian (and also Yellow-bellied) Flycatchers have grayish legs and bright green back plumage.

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• Finally, to go along with the confusing flycatchers, we'll conclude this update with a series of "confusing" fall warblers banded the last few days of the week. Of course, all are hatch year females (check back next week to confirm your species ID for the birds pictured below).

Last Updated on 08/20/04
By Adrienne J. Leppold