Showing posts with label Dickcissel. Show all posts
Showing posts with label Dickcissel. Show all posts

Tuesday, February 18, 2014



Wheatlands Farm
Grassland Birds, 2013
Swoope, VA

Part III - Dickcissels

**(V I D E O)**
http://youtu.be/AyoccGw4hmE


For the third year running Dickcissels returned in 2013 to Wheatlands Farm in Virginia's Shenandoah Valley. The spring soundscape shifts radically the morning the Dickcissels awaken the grasslands, singing and counter-singing in a pattern that hints at katydids calling to a summer night. From the day they arrive these mini-meadowlarks belt out their raspy salutes to dominate the grassland rap. You would have to have your mobile device in your ear to miss them.

For perspective, in the Shenandoah Valley during 2013 observers posted Dickcissel sightings on eBird  (http://ebird.org/ebird/map/)  at fewer locations than fingers on a woodworker’s right hand. In the entire 2,500 square-mile Valley there were only three Dickcissel hot-spots, meaning places where the birds were seen repeatedly. One of the hotspots was Swoope, Virginia, near Buffalo Gap and all but one of the Swoope observations occurred on Wheatlands Farm (the other was across the road).  

As we noted in Part I of this post, I like to think the Swoope Dickcissels are legacy birds from an era when you needed a herd of bison and two sticks to maintain grasslands. If Swoope can be said to have a tourist trade, a fair fraction of the photographers and fun seekers come to see the Dickcissels. You can find Swoope by traditional means but a GPS helps.

The Dickcissels were here in 2000, then not again until the three-years beginning in 2011. I discussed the excitement then with Kenn Kaufman  (www.kaufmanfieldguides.com) who offered an explanation for the 2011 Dickcissel irruption to the east of the Alleghenies:

"...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. "

The western drought was even more severe in 2012 when about two dozen Dickcissels sang at Wheatlands. In 2013 the drought concentrated and shifted westward; a half-dozen males called on Swoope.  

Naturalist and author Barry Kinzie (www.amazon.com/Birds-Roanoke-Valley-annotated-checklist/dp/B000715PFW)  visited Wheatlands during the 2012 Dickcissel takeover and voiced the hope that a “ nursery colony” of the birds might develop and persist after the droughts. That would be consistent with my speculation that Audubon’s "Black-throated Bunting" is channeling  a tribal memory of the Swoope grasslands, perhaps a traditional Plan B to be dusted off when the core western range is stressed.

The Dickcissels arrived on June 7th, likely adrift from the parched West. The males sang and did little else; the females strove and toiled, raising their broods, toting caterpillars first, grasshoppers as the nestlings grew (Bent’s Life histories).  The last Dickcissel song rang out on August 7th; that male perched silent for a few more days then faded, perhaps in the direction of Venezuela. When that happened early in August of 2012 I concluded the entire Dickcissel company had left – wishful thinking on the part of a farmer hoping to salvage a cutting of hay.

This year the males may have headed south in early August but the juveniles became the lawyers and lobbyists. They began to issue a contact call that comes across as P(x)T, with an sh in there somewhere, but no vowel. It was suggestive of, but different from, their mothers’ protest chips  and as the adult females drifted into silence the juveniles became the voice of the clan.  Throughout August and into September the calls of the juveniles betrayed their locations and made clear the Dickcissels were a presence still. You can hear this call on the attached video and you might find it useful in locating Dickcissels in late summer after the males leave (or hide and hush).

Purloining vintage Kaufman humor I’ll mention that the house at Wheatlands, built in 1813, celebrated its buffalo birthday this year, something of a … "bisontenniel" .  But the Europeans maintained the Buffalo Gap grasslands after the bison left, all except for a grove of trees surrounding the house, a sugar-maple island in a sea of grass. The yard trees are where the Dickcissel juveniles spent their last days at Wheatlands.  They quit the natal grass, the shrubs and briars of their fledgeling days, and became, for a fortnight, forest birds, P(x)Ting to a mother who had lost interest in their demands and perhaps had struck her tent as well. They made their own foraging trips into the adjacent pastures, plainly vocal regarding their new-found neglect.

Then, apparently surfing their own genetic GPSs, on September 6th the recruits were gone. Se fueron.

Thursday, November 21, 2013

Wheatlands Grassland Birds – 2013

Part One


In their 2013 breeding enterprise the grassland birds at Wheatlands Farm confounded and amazed. But as Flip Wilson used to say,

“ I’m going to tell you that story , but first I need to tell you this one so I can tell you that one.”

A discussion of grassland birds needs a sketch of grassland history and dynamics, which we cover in this first part; we’ll get to the 2013 adventures of the grassland birds in the next two episodes.
Wheatlands, a 165-acre beef cattle farm in the southern Shenandoah Valley, lies in the rain shadow of North Mountain, specifically to the immediate east of 4463’ Elliott Knob which lofts nearly 3000’ above the Valley floor.  In the lee of that prominence the annual rainfall averages 35 inches, ten inches less than the 45 inches lavished on the rest of Virginia. Thirty-five inches is a moisture regime favoring grasslands over deciduous forest and is only slightly more than the average for the tall-grass prairies that once carpeted Illinois and Missouri and Iowa – with a little help from the grazing ungulates and the peoples who invested in the “millennia of exuberant burning” chronicled by Charles C. Mann in 1491.(www.theatlantic.com/magazine/archive/2002/03/1491/302445)

It would be more accurate to say that at a location in temperate North America experiencing a 35-inch rainfall, woody plant succession is more easily arrested than at 45 inches. However, even at reduced moisture, plant succession is still as certain as gravity unless some force acts to suppress the trees and shrubs.  Humans, sponsoring a rich and mobile protein source in the form of grazing ungulates, have been that force since the Wisconsin ice receded 11,000 years ago. Perhaps for all of post-glacial history humans have managed the North American landscape to create grasslands where practicable, including much of the region east of the Allegheny Mountains and especially , I am inclined to believe, in the rain shadow of North Mountain.  That 20-square-mile enclave is beef cattle country today as it was bison country a thousand years ago. Buffalo Creek has cut a waterway through Little North Mountain creating Buffalo Gap which offered the bison summer grazing in the interior of the Alleghenies. Wheatlands Farm is at the center of North Mountain’s 35-inch rainfall arc.


*( V I D E O)*

Wheatlands Herd Management

For Apple devices
http://www.youtube.com/channel/UCsfBhrv4OOnJyAj0MDrucWw/videos


For Windows



I live at Wheatlands, so I muse upon the Buffalo Gap grasslands, their history and their legacy complement of grassland birds. I and a Border Collie named Benson tend a cow/calf herd of Charolais-Angus beef cattle 75 to 100 critters strong.  The Wheatlands cattle, like the bison, are grazers; they eat a mix of grass and forbs (non-grass herbs).  When they discover a woody sapling in a pasture they attack, chomping and stomping, horning and wallowing, ripping off branches and pawing the successional intruder into oblivion. I suspect the bison carried the same genetically-encoded chip on their wooly humps, the innate urge to destroy trees, perhaps sensing that trees are a threat to their grassland "salad bar" (a Joel Salatin term. Joel also lives and raises cattle in the North Mountain rain shadow).  The cattle may be desperate for shade but they will not suffer a sapling to grow in their pasture. Moreover, they eventually kill even the mature trees by clustering under them, rubbing off the bark, and compacting soil at the roots.

My interpretation is subjective, but the bovid inclination to work in concert with fire-wielding humans to create and maintain grasslands is clear enough.  I am comfortable with the conclusion that grasslands in temperate North America and other locations, modern and past, are typically the result of the ancient alliance of humans and bovid ungulates – cattle (genetically, auroches ) and bison. Remove the bovids from the equation and humans have no incentive to burn (or mow). Remove the humans and the bison (or cattle) eventually face reduced rations or at least a shift of diet to browsing, which requires a different gut chemistry than is typical of bovids. Remove both and the land reforests in half a human span (Godfrey, 1980).

From the standpoint of grassland birds, grazers are a blessing, if mixed. As they can stomp woody saplings they can also stomp on-ground nests. But as they munch along they tend to leave a grass/forb stand of varying heights which accommodates the birds’ foraging and nesting needs. Dr. Scott Pendleton, a veterinarian in Cadiz, Ohio, monitors Upland Sandpipers and Bobolinks on reclaimed mine land in Harrison County. He notes,

“All the successful Upland Sandpiper and Bobolink nests I have seen on these reclaimed mine lands are in sections which the mine owners lease to local farmers for grazing. The birds need stands of varying heights and densities which the cattle create. The challenge is to encourage farmers to delay mowing to let the birds complete nesting.”

Call the grasslands a stool, if you will, of the kind that furnishes seating and requires three legs – people, ungulates, and a group of birds which are obligate grassland breeders.  If the grasslands and the grassland ungulates knew a close ecological kinship with the humans of olden times so must the grassland birds. Over the millennia the Meadowlarks, the Grasshopper Sparrows, the Bobolinks, the Dickcissels must have been co-passengers with the bison on mankind’s grassland rollercoaster.  Management by birds of seed dispersal, insect pollinators, and food-source insects (grasshoppers et al) are surely vital functions in grassland economics, perhaps of importance equal to the contributions of people and bovids. The entire avian cohort must have learned to balance in the shifting winds of human-created grasslands in North America, riding waves of tribal warfare, weather events, climate shifts, and developments in food-production technology.  We must have in mind that pre-Columbian native populations in North America were large -- 20 to 40 million people at times (Mann, 1491)-- and the ability, the need, of those populations to manipulate the landscape carried massive ecological impact. Trackless virgin forests? Forget it. Even in the East. It is much more efficient to harvest bison in large herds on open grasslands than individual deer skulking in forests.

A hypothesis emerges; like the bison and the grasslands themselves, the grassland birds must operate in  a confederacy with mankind. Over time (people have been in North America for at least 16,000 years) the grassland birds have followed moccasin and hoof through wealth and want, shifting their ranges and schedules and diets with the fortunes of the grasslands of human creation. We see our birds, our surrounds generally, through a squinty lens of 500 post-Columbian years.  That is a very short slice (maybe 5% of the whole salami) of the era of people and their grasslands in North America. The dynamics have always shifted and calamity is likely no stranger, but it seems justifiable to see at least a blur of birds and bison on mankind’s grasslands over 500 or so human generations. 

A Krakatoan blast hit North America’s grasslands after 1492 in the form of diseases distributed by the Spanish.  Very quickly, most of the native human population was dead. There was no immunity to the new pathogens and there was little immunodiversity in the native genetic endowment because the natives of the Western Hemisphere were descendants of a small number of adventurers who crossed the Bering Land Bridge. In Guns, Germs, and Steel Jared Diamond reports,

"Throughout the Americas, diseases  introduced by Europeans spread from tribe to tribe far in    advance of the Europans themselves, killing an estimated 95% of the pre-Columbian  native American population. The most populous and highly organized native societies in North America,  the Mississipian chiefdoms, disaappeared in that way between 1492 and the late 1600s, even before Europeans themselves made their first settlement on the Mississippi River. "

The scheme which had created and maintained the grasslands must have collapsed abruptly. Much of the continent, especially the well-watered East, quickly reforested.  Some understand the volume of atmospheric carbon sequestered in this sudden reforestation to be sufficient to account for the 200-year global temperature drop beginning in 1650 known as the Little Ice Age. By the time the English took an interest in penetrating the continent’s interior in the early 1700s a newly established canopy covered dark corridors of forest that shrugged as if to ask “Grasslands? What Grasslands?”

In the 1700s the English, and others, cleared a lot of forest and created a lot of new grasslands.  By 1900, 75% of the Piedmont was under plow or pasture.  In the accounts of A.C. Bent, the grassland birds recovered somewhat.  But by 1980 only 25% of the Piedmont was cultivated – we, especially we southerners, abandoned our farms wholesale and put them in the hands of the wood products companies creating a desert of row-planted pines.  The grassland breeders vanished from those lands.  Bent refers to a reduction in the Dickcissel’s presence in the East beginning in 1900; the 1980 edition of Peterson’s Field Guide to the Birds notes “formerly bred along seaboard Mass to S.C.”  The Dickcissel, an obligate grassland breeder, has responded to the abandonment (and reforestation) of eastern farmland by vacating much of the East. Other grassland endemics, including Bobolinks, are reduced as well.

Another disruption now threatens the grassland birds – climate change.  Beginning in 2011 and through the 2013 nesting cycle, there has been chronic drought and fire in the Dickcissel’s core breeding range, the traditional prairie grasslands.    The results are apparent in one corner of one valley in Virginia and probably at other locations to the east of the Alleghenies. An informed argument (Kaufman, private correspondence, 2011) suggests that drought-associated pressure on the core breeding range in the Great Plains forced some of the birds eastward. For the first time since 2000, Wheatlands hosted Dickcissels in 2011, probably a half dozen, then more than two dozen singing males in 2012. Numbers were down in 2013 to the 2011 level as the drought shifted westward.

We can hope that the Dickcissels that fled the western droughts in 2011-2013 to nest in the southern Shenandoah Valley may rekindle an interest that will persist even when drought spares the West. That depends on the health of the eastern grasslands and on the compatibility of our farming methods with the birds' breeding needs – in other words, the Dickcissels not only need to nest in the East, they need to nest successfully to recruit a cadre committed to the East.  Because nearly all remaining eastern grasslands are on active farms under intensive production, many nests go through hay-making machinery.
   
In the next two parts of this post we will detail the 2013 nesting cycle of the Bobolinks and Dickcissels at Wheatlands. Their unexpected schedules and behaviors may add an increment to our understanding of these birds with an ancient link to man.


Sunday, July 7, 2013

A New Lease on Life

*(VIDEO)*
Upland Sandpipers, Harrison County, Ohio


“Natural Grade”.

It’s what the natives of Harrison County, Ohio, call the shape of the land left after epochs of erosion of the once mighty Appalachians. That shape is unusual now in parts of Harrison County because the coal interests have deep mined, and high-walled, and strip mined 80% of some townships. The recontoured lands – those mined after the law required smoothing and seeding -- show a bloated uniformity contrasting with the angular “natural grade” remnants, some forested. The recontoured lands grow grass tufted with the alien invasive, autumn olive.

The dozerscape does not affront the grassland birds of Harrison County. These synthetic hills offer safe breeding harbor to Grasshopper Sparrows; Savannah Sparrows; Henslow's Sparrows; Vesper Sparrows; Horned Larks; Eastern Meadowlarks with dialects suggesting Dickcissel’s introductory notes; Bobolinks; and, wailing out of the mists of myth, Upland Sandpipers! What this polyglot singing on the dozered slopes says is that whatever mix of plants the coal company planted for erosion control evidently is acceptable to the native grasshoppers and other insects, for these invertebrates feed a multitude. It is difficult to imagine a more vibrant community of grassland birds.

After the first round of strip mining, the company began liquidating the mined-out land in tracts ranging from 5 to 200 acres. Then two things happened; a new technology enabled the re-stripping of parts of the land for coal that once had been deemed inaccessible or inferior and the Marcellus Age dawned. The coal company lost all interest in selling and made plans to further work the holdings, happily stripping and fracking into the 21st century. The upside, if there can be an upside to a land torn by extraction, is land stripped before the reclamation law and scarred by 80 foot highwalls will be reclaimed to something approximating natural grade and large tracts of open grassland will be formed or preserved. 

But what to do with the tracts of grassland while they are warehoused for future exploitation? Leasing them to cattle farmers seemed logical; that generates a little revenue and it puts someone on the land with a security interest.  Grazing the reworked lands with cattle in large boundaries also happens to mimic the imprint of bison on the land – enriching soils, diversifying the grass and forb stands and, most importantly for the grassland birds, creating grass stands of varying heights and densities. In the words of Dr. Scott Pendleton, an accomplished field naturalist and a veterinarian at Cadiz Animal Clinic, a large-and small-animal practice near the Cadiz, Ohio, airport:

“More than half our Henslow’s nests and all of the Upland Sandpiper nests are on coal company land that has been grazed. Also, the sandpipers and their hatchlings like to forage on the newly-cut hay ground. We are working with the leasing farmers to schedule cutting and grazing after June 20th when the young Uppies are out foraging with the adults and most of the passerine birds have fledged.”

The take-home points from this expedition to Harrison County, Ohio, are that:
The only place in the county to host breeding Upland Sandpipers, an Ohio Endangered Species, is recontoured strip-mined land, and
On that recontoured land the Upland Sandpipers show a clear preference for grass stands that have been grazed by cattle, a preference they share with many other grassland birds.



Does Harrison County offer a template for an exciting conservation initiative?