In Volume II of the Stokes' "A Guide to Bird Behavior," 
they write about a visual display they call a "Wing-spread."  
They show the White-breasted Nuthatch with its wings 
outspread and beak pointed up, tail spread, and describe 
it as swaying from side to side.  This is,  "Given near a nest 
or feeder when the bird is in competition with other birds or 
mammals." 

Today our male nuthatch came down a mulberry tree 
towards a ground feeder.  Anchored on the trunk maybe 
two feet above the occupied feeder, wings and tail spread, 
head downward, he vibrated his wings and rotated smoothly 
and slowly; moving like a little mechanical pendulum,
back and forth.   It was an impressive and decorative
display which lasted for several seconds, and ended when 
the House Sparrows below flew up; and he flew as well.   


Elise Kreiss
Baltimore, Maryland