Peregine Falcon & Barn Swallows

Lou Shomette (lshomett@maa.org)
Fri, 01 May 98 12:15:42 EST


     Hi all,
     
     Yesterday, while waiting for fellow birder Tim Boucher at the bridge 
     to Roosevelt Island in DC, I saw something I'm not quite sure what to 
     make of it...
     
     Barn Swallows are building nests below the bridge that crosses over 
     the Potomac to Roosevelt Island.  After skittering over the water, 
     searching for insects, the Swallows formed into a group and headed in 
     the direction of Rosslyn about 30 feet above treetop.  A few seconds 
     later, a Peregrine Falcon came from the direction the Swallows were 
     heading, crossing over the Potomac.  Immediately following the 
     Peregrine was the group of Barn Swallows.  They weren't mobbing the 
     Peregrine like crows mob hawks, but the definitely seemed like they 
     were trying to drive the Peregrine away.  Half way down the island the 
     Barn Swallows returned to their nesting area.
     
     Has anyone experienced anything like this?  Is this a common defensive 
     behavior for Swallows?  Any help would be appreciated.
     
     Lou Shomette
     Columbia, MD
     
     PS  We had several Wood Thrush, Veery and Eastern Towhees.  Lots of 
     Yellow-rumped Warblers, Northern Parula, Ovenbird and a Scarlet 
     Tanager.  Also, my first Hummingbird Clearwing moth of the year.