Ticks and birds

[MaryHuOT@aol.com]

I may have seen something a while back about this, but I can't remember for 
sure.  Today at lunch time I was watching the house finches at my back yard 
feeders--checking for eye problems.  I noticed a female bird with something 
on the back of it's head.  I couldn't figure out what it was--it was round, 
dark gray, and at first I though it was a patch of skin with no feathers.  
then I realized it was protruding from the back of the bird's skull.  I 
finally decided it looked more like a tick than anything else--a big inflated 
tick. The bird was acting kind of sluggish and no wonder since the thing was 
about the size of a large green pea! I have not noticed a tick on a bird 
before.  Is this common?    Reply off list is fine.

Mary Bridges
Goldsboro, NC