FreeLists / va-bird / [va-bird] Puzzled about nighthawks

[wdunson@xxxxxxxxxxx]

This time every year I am puzzled by the behavior of migrating nighthawks.  
They regularly arrive in large numbers over our farm in SW VA in the early 
evening/late afternoon (about 4 miles west of Galax, about 1 mile from the New 
River where rt 94 crosses it, and about 8 miles north of the Blue Ridge 
Parkway) during the third week of August.  We have several days of large 
numbers, but not consecutive days, many days of lesser numbers and then none.  
The bulk of the migration seems to remain a mystery.  There are some 
tantalizing clues:  Jim Keighton saw a kettle of nighthawks very high late one 
afternoon, and Roberts reports seeing nighthawks descending in early morning to 
land in bushes.  Other members of our bird club see no or very few nighthawks 
at their locations so it appears that there are migratory pathways that are 
used every year.  So what is happening?  Are the nighthawks using thermals to 
migrate during the daytime, and often so high as to be un-noticeable?  Are t
 hey al
so migrating at night when they are not seen?  Of course there is also the 
famous tendency of nighthawks to fly in many different compass directions, and 
not necessarily South.  I was expecting a big increase when the front recently 
passed over with resulting Northerly winds, but this did not happen.

If anyone can enlighten me on the mysteries of nighthawk migration I am all 
ears!

Bill Dunson
Galax, VA

2005 nighthawk counts:

8/20/05-      8
8/21/05-  100 +
8/22/05-  510      from 6:06-7:32 PM

2006 nighthawk counts:

8/16/06-       0      from 7:35-8:35 PM
8/17/06-     23      from 6:15-7:35 PM
8/18/06-       1      from 6:55-7:55 PM
8/19/06-     25      from 6:00-7:05 PM
8/20/06-   570      from 5:25-6:23 PM
8/21/06-     27      from 5:45-6:45 PM
8/22/06-      1       from 5:54-6:54 PM
8/25/06-      2       from 5:35-6:35 PM
8/26/06-    28       from 6:15-7:05 PM
8/27/06-    76       from 6:15-7:55 PM
8/28/06-  279       from 6:30-7:15 PM
8/30/06-      1       from 6:10-7:10 PM
9/1/06-        0       from 5:55-6:30 PM
9/2/06-        5       from 6:20- 7:20 PM


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