Dispatches from Buffalo Gap

Male Dickcissel singing near nest on Wheatlands Farm

Swoope, VA

July 10, 2011

 In olden times bison grazed in Virginia's Shenandoah Valley, as the written histories chronicle and as the place names tell us. As I write, Buffalo Gap controls the view out my window as it once controlled the lives and economics of the peoples who lived here between the melting of the Wisconsin Ice and the arrival of Europeans. Through Buffalo Gap, European settlers cut a roadway to the Ohio River called the Parkersburg Turnpike, then in 1853 the Virginia Central Railroad (now CSX), passing through this farm on its way to the Gap, connected tidewater Virginia with the world beyond the Allegheny Mountains. The next water gap up the ridges to penetrate the Appalachians is the one cut by the Potomac River at Harpers Ferry, 100 miles to the north. The comparable gaps to the south would be those of the James River and its tributaries.

But in a sense there are no gaps in the Alleghenies comparable to Buffalo Gap for it is possible, as peoples and bison have discovered, to trek through the maze of the Appalachian highlands by entering Buffalo Gap at the western margin of the Shenandoah Valley and ultimately finding the eastern edge of the prairie lands across the Ohio River.  There is an argument that New York’s Mohawk River similarly cuts the highlands for access to the western grasslands, a geography which made possible the Erie Canal and the enduring commercial primacy of New York City. The buffalo reached eastward to their eponymous town on Lake Erie but do not seem to have taken advantage of the Mohawk passage. So, during historic times Buffalo Gap may present the only example of American Bison regularly penetrating the entire width of the Appalachian Mountains to access eastern grasslands.

Buffalo Gap

Village of Swoope, Virginia between cattle and Gap

 

For now, I am powerless before the urge to speculate that Buffalo Gap offered a historic avenue connecting the life schemes of the East with the great grasslands of the interior. The presence of the bison suggest this connection, for the bison must have (or probably did, or may have) pioneered their way eastward from the prairie grasslands. Once here,  to speculate further, the great ungulates and their human sponsors enhanced the grasslands in the western Shenandoah Valley, particularly the section (where I live) lying in the deep rain shadow created by North Mountain of which the local prominence is Elliott Knob at 4464 feet. The annual rainfall here is just 35 inches; ten inches below Virginia's average, and closer to a grassland moisture regime than to that of deciduous forest. Still, plenty of trees grow in the rain-shadowed Upper (southern) Shenandoah Valley, and they must have encroached upon the grasslands.  Therefore, goes my argument, the Indians must have maintained grasslands here with fire, for prior to the chemical warfare now practiced to suppress broad-leafed plants, fire was the only means of maintaining grassland; that is, of arresting the normal course of plant succession which would eventually have reforested the area. The bison spilled out through Buffalo Gap to winter in the Shenandoah Valley then returned to graze the high pastures in the Alleghenies in summer.  That is my theory; underpinned by

- a passage across the Appalachian Highlands accessible through Buffalo Gap, 

- the name Buffalo Gap and references to bison here in written history, 

- the locality’s reduced rainfall owing to the rain shadow of Elliott Knob, a rainfall regime which would have helped the Indians  maintain the grasslands, and

-  a certain grassland bird which keeps returning, possibly to check out present conditions against those encoded in its genetic endowment.

I am holding a signed and cherished copy of the 1947 edition of Roger Tory Peterson's A Field Guide to the Birds.  Regarding the Dickcissel, an obligate grassland bird, Peterson says " Breeds in Prairie States e. to ... w. Ohio..." Peterson revised his guides in 1980, separating eastern and western volumes and adding detailed range maps prepared by his wife, Virginia. I recall her studio, romantically adjacent to Roger's, stacked with maps and reports from which she sifted her interpolations of the birds’ ranges; Virginia Peterson took her cartography seriously. She shows the Dickcissel's fundamental breeding range as the prairie lands between the Rockies and the Appalachians, but she added two dots suggesting disjunct ranges east of the Appalachians which she calls "Localized Breeding Areas".  One of those dots, the larger, appears to be centered over Fredrick, Maryland.  The smaller dot covers my farm and a few (dozen) others in the lee of Elliott Knob and within sight of Buffalo Gap.

Roger Peterson wrote the first field guide to birds and in so doing presented to us the field guide concept. Before the Peterson guide appeared in 1934, if you were interested in birds you loaded up with number 8 shot and blew from the branches a hatfull of migrating warblers. In the view of many, Peterson started the conservation movement by giving all of us access to non-lethal birding and by making nature study a considered passion rather than a blood sport. While Peterson influenced many worthy successors, his depictive mantle devolved upon an accomplished interpreter of natural history named Kenn Kaufman.  Kenn published his Field Guide to the Birds of North America with Houghton Mifflin Harcourt in 2005, an effort now developed into a series of guides to life forms no less inspiring than the series edited by Peterson, but with updated perspectives.

Kenn's guide shows the Dickcissel's core breeding range as approximately the original prairies, with shadings of intensity and broken lines for irregular expansions. In a recent conversation he described the bird as "eruptive", suggesting it may, at its pleasure, show up in substantial numbers outside its accustomed breeding range.  He offers an explanation for this year's eruption, perhaps based on the bird's displeasure,

"...this is an interesting season for grassland birds.  I think it's driven at least partly by the extreme drought in the southwest and the western plains ... only a part of the Dickcissel's normal breeding range is under severe drought conditions, but it seems to be enough to have caused a shift, and a number of areas farther east are reporting higher numbers than usual.  Certainly they're unusually numerous in Ohio. "

For now I will call the Dickcissel’s 2011 eastern showing (the first on this farm during the present millennium) the Buffalo Gap Eruption and I hope that you will prove me wrong.  I hope the Dickcissel compensates for  its western stresses by nesting widely in  our remaining eastern grasslands and that you will cup hands to ears to listen for the "dick...CIS,CIS,CIS" signature as you pass pasture. It likes tall, uncut grass (not pasture grazed hard or recently-cut hay ground) and I do not hear it calling here in pastures which have been herbicided. Please share your findings; is the bird breeding in substantial numbers outside Ginny Peterson's  Buffalo Gap Dot?  Is it breeding in the Fredrick Dot?   Dickcissels singing on territory anywhere east of the Appalachians (as they once did, if sporadically) could be important, possibly as harbingers of climate change or perhaps in support of certain theories which offer the bird as an indicator species for historical grasslands.

Best regards,

Michael Godfrey