By LeJay Graffious
Maggie Perl returns from the net lanes with several brown paper bags, each labeled with a bird alpha code and twisted at the top to create a safe air space for the bird being transported. She hands them over to me, the bander on duty. I do a quick scan of the codes to triage the banding order. One is labeled BLPW, the bander’s alpha code for Blackpoll Warbler. Generally, this code is the first two letters of the first word and the first two letters of the second word of the bird’s name. For example, a Northern Cardinal would be abbreviated as “NOCA.”
But there are exceptions when there is overlap. I know, from years of experience, the Blackpoll takes a 0-size bird band. Birds’ tarsi vary in size, so bands come in different sizes to fit loosely, but not slide over the joints, thus not interfering with the birds’ movements. My last banded bird was a 0-size band. To simplify record keeping, I want to continue with the same size band, so I extract the bird from the bag with a bander grip.
I confirm Maggie’s identification and proceed with the banding process. I next place a band on the tarsus and record the band’s nine digit code and the bird’s alpha code. This particular bird now has an individual identity and a story begins. By wing length and pattern of the dusky or black in the back feathers, I determine this Blackpoll is a hatch-year male. I confirm the age by looking at the skull. A few drops of water on its head allow me to easily part the wetted feathers, revealing patterns of pink and white seen through the skin.
Pink areas are unpneumaticized windows confirming a hatch year bird. The process of a bird developing hollow, strong air-filled bones is called pneumaticization. As calcium struts form between the inner and outer layers of skull bones, these windows fade to white. With his nine digit code and pertinent data recorded, the bird is released to continue his journey.
As 2810-36780 flies over the brink of the Allegheny Front, I wonder at its journey. Jack Conner wrote in his book, Season at the Point, “Almost everything we know with certainty and precision about bird migration has been discovered or proven through banding, and it is not an exaggeration to say that the numbered leg band has been as important a tool in the science of avian migration as the telescope has been in planetary astronomy.”
We know Blackpoll Warblers breed coast to coast in black spruce and tamarack forests in Canada’s and Alaska’s boreal forests. Could this bird be from western Alaska? Draw a straight line from Nome, Alaska to Sao Luis, Brazil. You may be surprised that it crosses West Virginia.
The Allegheny Front Migration Observatory bands more Blackpolls each year than all of North America’s other banding stations combined. As of the beginning the 2018 season, 33,947 of the 270,265 birds banded during the history of the station have been Blackpoll Warblers. Of these, only two have been foreign recaptures. One banded in September 1976 was found near Kalispell, MT the following year. Bob Dean banded a hatch year bird in September 2006 that was recaptured in Santa Marta, Colombia in October 2008. This is a small return on the large investment of time and effort but, when taken in aggregation with all records, a picture emerges of migration patterns.
Ornithologists are piecing the Blackpoll puzzle together. The Cornell Lab’s allaboutbirds.orgwebsite states, “This long-distance athlete weighs less than half an ounce (12-13 grams) yet makes the longest overwater journey of any songbird—nearly 1,800 miles nonstop over the Atlantic Ocean to its wintering grounds.” They first do an eastern journey across the continent north of the Great Lakes to the coast, then some turn southeast over the Great Lakes through WV. This journey can be nearly 3000 miles for some.
Then they wait along the coast from Maine to the Carolinas for a night with a brisk, northerly tailwind after a cold front passes. The normally 12 gram birds, now fueled up to around 19 grams, head out to sea, climb to 5000 feet and, aided by northwesterlies, fly toward their winter home. Midway, around Bermuda, they pick up the subtropical trade winds which carry them southwest. They make landfall on the north coast of South America. Scott Weidensaul wrote in Living on the Wind: Across the Hemisphere With Migratory Birds, “… an overwater trip of about 2000 miles – a passage with no rest, no refueling, no water, during which each bird will have flapped its wings nearly 3 million times.” Yet, they have not reached their destination! They spread out through South America adding up to another 1,500 miles. Then in April, they reverse course back to the breeding grounds. During the northern trip they cross the western Caribbean or the Gulf of Mexico.
I marvel at 2810-36780’s travels. Being hatched this summer in the north, he has never made this trip before. Yet young birds migrate at different times than the adults. The whole flight plan is preprogramed in their genetic code. The rigors of migration take their toll. Only one in six birds survive the first year. That is why the work of conservation groups like the WV Highland Conservancy is so important.
Meanwhile, the story of the Blackpoll Warbler, number 2810-36780, continues. Hopefully, he will make many trips between breeding and winter grounds. And, if we are truly lucky, he will be re-found somewhere along his life’s path, filling in a new chapter in his story and adding to the growing body of knowledge of North American ornithology.