FreeLists / va-bird / [va-bird] Western Fairfax Co, 6/8/02

[KurtCapt87@xxxxxxx]

VA BIRDers,

I simulated a Breeding Bird Survey run in Western Fairfax County this 
morning. For those unfamiliar with this survey technique, I made 3 minute 
stops to count all the birds at that location and then repeated the process 
at half mile increments along an almost continuous path.  The route fell 
short of the required 50 stops - I did 30 stops, but my interest today was 
mainly Fairfax Co.  (I will determine if 20 more stops can be added.)   64 
Species were recorded.

I started on Bull Run PO Road, near the border with Loudoun Co mainly to pick 
up the Whip-poor-wills at about 0515.  (This is the location for the 
Short-eared Owls, etc.)  I deviated at that point and went up the road about 
0.5 mile to the corner in Loudoun Co. for the next point since it seemed like 
an obvious spot to have started and then back-tracked south into Fairfax Co, 
continuing south until the end of the road at Bull Run Regional Park, a total 
of 16 stops.  Then, I drove north and a bit east to Pleasant Valley Parkway 
and started the survey northbound from the intersection with Eagle Tavern 
Way.  I ended at Pleasant Valley Rd and Rt 7, Leesburg Pike, at a business 
park.  Total time was about 2:45 hours.

The habitat is somewhat mixed - alot of successional farm fields, some wood 
lots, new suburban housing developments, developments in progress, turf 
farms, a relatively new golf course, and a small business park.  In sum:  
This area is in a state of change as the DC/Fairfax Co population core 
expands outward.

I have compared the numbers, appropriately scaled, to those of 2 other 
piedmont BBS routes in the No. VA area (David and Davidsonville) and found 
that today's results are very similar and fit into the 10-year average range 
for those routes quite well.  This was a bit surprising to me, but it appears 
that the conclusion to draw is that piedmont diversity is still present in 
western Fairfax Co.  I note that the route has a few minuses as well as a few 
pluses.  For example, since the area does not have alot of farm fields for 
cattle, hay, etc, there is small concentrations of some of the important 
field birds such as Grasshopper Sparrow (not recorded), Red-winged Blackbird 
and Eastern Meadowlark.  Yet, some of this habitat supports enhanced numbers 
(greater than a factor of 2 of the 10 year average range for the other 2 BBS 
routes) of species like Whip-poor-will, Acadian Flycatcher, Willow 
Flycatcher, E. Phoebe, Yellow-throated Vireo, Red-eyed Vireo, Tufted 
Titmouse, White-breasted Nuthatch, Blue-gray Gnatcatcher, Prairie Warbler, E. 
Towhee, and Field Sparrow.  I suppose that part of the reason for the 
enhanced concentrations of the above birds may be due to the overgrown, 
successional old farm fields found along the route.

There were a few notable misses, Yellow-billed Cuckoo, Yellow Warbler, 
Grasshopper Sparrow, and any oriole.  Except for the case of the Grasshopper 
Sp, I am not sure I understand the reasons for these misses other than the 
concentration of these species is low along the route.

The data for the 30 stops follows.

Kurt Gaskill

Great Blue Heron 1
Turkey Vulture 1
C. Goose 4
Red-tailed Hawk 1
Am. Kestrel 1
No. Bobwhite 8 (on-target average with the other piedmont surveys!)
Killdeer 3
Mourning Dove 15
Barred Owl 1
Whip-poor-will 2 (more singers out there, its just getting a bit too light at 
0515)
Chimney Swift 10
Belted Kingfisher 1
Red-bellied WP 5
Downy WP 5
No. Flicker 5
PIleated WP 2
E. Wood Pewee 7
Acadian Flycatcher 5
Willow Flycatcher 5 (the business park at Rt 7 has 2 widely separated singers)
E. Phoebe 7
Great Crested Flycatcher 4
E. Kingbird 3
Yellow-throated Vireo 3
Red-eyed Vireo 14
Blue Jay 12
Am Crow 40
Fish Crow 2
Purple Martin 1
Barn Swallow 5
C. Chickadee 6
T. Titmouse 15
White-breasted Nuthatch 4
C. Wren 6
H. Wren 8
Blue-gray Gnatcatcher 8
E. Bluebird 4
Wood Thrush 9
Am Robin 35
Gray Catbird 9
No. Mockingbird 15
Brown Thrasher 4
E. Starling 34
Cedar Waxwing 1
No. Parula 1
Pine Warbler 2
Prairie Warbler 9
Ovenbird 1
Com. Yellowthroat 9
Yellow-breated Chat 2
Scarlet Tanager 3
E. Towhee 14
Chipping Sp 6
Field Sp 16
Song Sp 9
No. Cardinal 27
Blue Grosbeak 3
Indigo Bunting 19
Red-winged Blackbird 7
E. Meadowlark 2
Com. Grackle 29
Brown-headed Cowbird 9
House Finch 9
Am. Goldfinch 9
House Sparrow 5


You are subscribed to VA-BIRD. To post to this mailing list, simply send email 
to va-bird@xxxxxxxxxxxxxx To unsubscribe, send email to
va-bird-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field.