• While we added quite a few new species to our spring totals for the season, numbers were still well below average.  The total of 380 birds banded since March of this year is our second lowest ever for the period, just behind the 363 birds banded in the very first spring season at Powdermill in 1962.  We attribute our comparatively low banding total this spring (in fact, in the past several migration seasons) to reduced numbers of Dark-eyed Junco, American Goldfinch, and Evening Grosbeak, species which often have been caught here in very large numbers.  Evening Grosbeak numbers have changed as a result of a range wide retraction to the northwest, perhaps in response to spruce budworm control measures in northeastern Canada.  American Goldfinch is well known as an irruptive species, prone to wide annual variation in numbers.  However, recent declines in the number of migrant and wintering Dark-eyed Junco at Powdermill have yet to be explained.  Historically, we have banded as many as 400-500 juncos in spring.  As recently as five years ago, spring totals declined to the low hundreds, but within the last few years our spring (and fall) banding totals have not even exceeded double digits.  Given the increasing conservation concern about the condition of boreal forested habitats in North America, perhaps Dark-eyed Junco may become an important indicator species.  For more information on conservation efforts in the boreal forests, please visit the boreal forest songbird initiative website.

• Notwithstanding its comparatively low spring banding total to date, the 93 Dark-eyed Juncos banded gave the species the number one spot for birds banded at Powdermill this spring.

 

 

Weather certainly has played a role in the timing of arrivals and number of captures for many species this spring.  It has been the driest April on record thus far in the Ligonier Valley (where Powdermill is located), with our last recorded precipitation on Sunday, April 3rd, in the surprising form of five inches of wet, heavy snow!

Thankfully, by Monday it had all but melted away, as temperatures rose into the 50's and we prepared for our first of two bander development workshops this spring.  We welcomed Cheryl Deane from New York, Lisa Abernathy from Ohio, Jessica Maggio from Maryland, and Lannie Graham from Virginia for our first ever beginner banders workshop.



While we intentionally scheduled this beginners workshop during a time of the season when catches tend to be lower, the week still brought many firsts for the season, including the after third year male Yellow-bellied Sapsucker in the photos above and below.  Unlike passerines, woodpeckers can be aged beyond two years because they retain up to three generations of primary coverts at any one time.  This bird, in particular, was likely even older because the oldest generation of coverts did not appear to be juvenile.  In addition, Pyle (1997) states that adult YBSA molts are seldom (if ever) complete.  Nonetheless, because these distinctions can be very difficult to make, we conservatively aged it as an ATY.

• This after second year female Eastern Bluebird was another new species for the season, as was....

• this second year female Belted Kingfisher banded on Thursday, April 7, our first kingfisher since last spring.  Note the worn juvenile feathers in the upper breast band inner mixed with some molted bluish feathers.  Females are identified by a complete lower chestnut breastband.

• One of three Eastern Towhees banded this period is pictured below, a close up of the eye of this second year male.  In addition to, of course, molt limits, eye color in EATO can be relatively helpful in ageing birds, even for birders in the field.  Molt limits often occur in the alula or carpal covert and also among the inner secondaries (i.e. tertials are frequently molted) with the eye of younger birds tending to be more red/orange with a gray cast, differing from the deep scarlet or blood red eye of an older adult.

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• We have experienced a decent flight of chickadees during the first half of this month, which should have come as no surprise given the irruption last year (see October 2004 past pictorial highlights).  Our beginner workshop participants, on the other hand, were probably a little less enthusiastic about seeing so many chickadees in the nets (not one of the easiest species to learn banding techniques with), in particular, the "gross" one shown in the photos below!

• This bird was host to an endoparasite which, historically, we have called anal or, more technically, cloacal flukes.  In the classic, Fleas, Flukes, and Cuckoos by Miriam Rothschild (1952), she describes mud flats and saltings as excellent habitat for flukes, highlighting wading, water birds, and ducks more likely hosts for these flatworms than landbirds.  Roundworms, on the other hand, are best known for parasitizing landbird hosts.  We admit to not having much expertise with the hundreds of species of parasitic worms and their life cycles and would certainly be interested to hear from any avian parasitologists who might better be able to classify these "anal flukes."  While parasites like the ones infecting this chickade will not cause direct mortality in any way, this bird is almost certainly more susceptible to malnutrition, predation, and other stresses.

• Continuing on with our "gross" birds of the month, we recaptured this Red-winged Blackbird with a bad case of "scaly leg," just in time to entertain a visiting college class during a banding demonstration.  Once thought to be a fungus, it is actually caused by small mites that burrow under the skin and remain there for their entire life cycle.  A disease like this would cause certain death if it infests the face, bill, or nasal passages, but for now it appeared restricted to the feet and legs of this bird.  It's interesting to note how the disease affected the growth and subsequent wear of the toenails in the bottom photo (undoubtedly,  preventing the bird from using its left foot in normal ways that would have worn its toenails down).  In cases like these, banders should always be sensitive to further agitation that a band could cause.  We certainly would not have banded this bird had it not been a recapture and did not remove the band only because it did not seem to be exacerbating the condition on the banded leg.

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• Two White-throated Sparrows, banded only four days apart, showed very different degrees of prealternate head molt.  The second year bird in the top photo was caught on April 10th and the very motley looking second year bird in the bottom photo was caught on April 14th.

• Lastly, after hearing them singing around the banding lab for nearly a month, we finally caught our first Louisiana Waterthrush.  This adult male, who was banded at the lab on April 17 , 2002 as part of the ongoing study of LOWA breeding biology and sensitivities to acidified streams, was recaptured twice that year as part of a breeding pair on Powdermill Run and recaptured 7 times since around the banding lab in 2003 and 2004.  He is now, at least, four years old

• To conclude, we would like to thank all of our workshop participants for a great training workshop week, their patience and understanding during some of the week's activities and we wish them luck as they continue to advance their banding skills from the foundation given here at Powdermill as they pursue other banding interests and ornithological careers.

 

 

We also thank Mike Comley, Carroll Labarthe, Molly McDermott, and Matt Shumar for their help with banding over the last two weeks.

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Last Updated on 4/23/05
By Adrienne J. Leppold