Mockingbird Upchucking Behavior

I was photographing a Mockingbird (thanks Peter) over the weekend and he was eating something from the ground... at one point it stopped and "coughed" up what appear to be 3 seeds. I certainly have never seen this behavior before... and thought that they let the berrys run their course through their system? Anyone got an explanation on this? Thanks!

- Luke

Very interesting. I've seen birds consume grit to assist in digesting foods and have seen other species regurgitating seed and sometimes insects to feed their young ,but I can't explain the behaviour . Perhaps it was sick and couldn't digest the seeds properly?

Great POV of the action Luke, interesting post here...

Maybe eating fruits, separating the fruits from the pulp in the stomach, and regurgitating the seeds?
This is a Northern Mockingbird, not a Gray Catbird.

Peter - Thanks for pointing that out. Can't believe I messed that one up... I obviously know the difference....

- Luke

I don't know what's going on here but I've seen mockingbirds do this on occasion. Here's an ancient film shot taken in Florida, probably in 1984, of a mockingbird "playing" with a seed or something.

I've also got a shot of a Loggerhead Shrike expelling a pellet just like a hawk or owl does.

I haven't edited it yet because I am so far behind on processing but I have images of a Robin in Montana taken in the early fall expelling a seed or some thing too. I'll try to edit it later and post it.

On more than one occasion I have seen Eastern Kingbirds regurgitate the pit from chokecherries after eating them.

Here is the Robin image I mentioned earlier, the Robins and Waxwings were feeding on chokecherries. I saw the pit or whatever it is fly out of the bird's bill, but didn't get an image of that while it was in the air.