June, et. al.,
      My main point was that this cowbird was too old to determine it's host 
species.  Associations mean nothing.  You can only determine the host by 
finding cowbird eggs in a nest or watching adults feeding cowbird nestlings 
or fledglings and even this can be tricky because there are records of birds 
feeding fledgling cowbirds that they didn't raise.
      The other point is that there are very few records of cowbirds 
parasitizing House Sparrow nests.  There are two reasons for this: (1) House 
Sparrows build enclosed nests( cowbirds prefer open nests) and (2) House 
Sparrows feed their young by regurgitation.  This is also the reason House 
Finches and goldfinch are not good cowbird hosts.

Paul Woodward
Fairfax City, VA