A Willet Expelling a Pellet

Yesterday I got a shot of a Willet expelling a pellet.  It’s a behavior I’ve seldom seen and rarely photographed because it typically happens very quickly, many birds  don’t do it at all and it often occurs only once per day or so with many species. 

A pellet, sometimes referred to as a bolus, is a clump of indigestible material that is formed in the crop and eventually regurgitated.  Depending on the diet of the bird it may be made of feather, bone, fur and/or chitin from insect or crustacean exoskeletons. 

 

Canon 7D, 1/4000, f/6.3, ISO 500, 500 f/4, 1.4 tc

At first I wasn’t taking many photos of this Willet because its lower legs were cut off by the rock perch but I did adjust my settings for quick action in case it took off or performed some other interesting behavior. 

 

 

Canon 7D, 1/3200, f/6.3, ISO 500, 500 f/4, 1.4 tc

The first indication I got that something might happen that would be interesting to photograph was when the bird pulled down its neck and there was a slight bulge in the throat.

 

 

Canon 7D, 1/3200, f/6.3, ISO 500, 500 f/4, 1.4 tc

Then the Willet began trying to expel the pellet. 

 

 

Canon 7D, 1/3200, f/6.3, ISO 500, 500 f/4, 1.4 tc

What happens next appears to look almost like a gagging reflex.

 

 

Canon 7D, 1/3200, f/6.3, ISO 500, 500 f/4, 1.4 tc

The pellet popped out so quickly that I didn’t even see it through the viewfinder and didn’t know if a pellet had actually been expelled until I got home and looked at the images on a large screen.   Based on the dark color of the pellet I assume it to be made mostly of insect exoskeletons that these birds are eating on their nesting grounds higher up on Antelope Island and relatively far from the shore of the Great Salt Lake.

I was surprised by how small this pellet was in relation to the size of the Willet and by how quickly and easily it was expelled – it only took a couple of seconds.   I once photographed a Northern Harrier struggling mightily to expel a very large  pellet for over 30 seconds and it appeared to almost choke on the pellet before it was finally expelled.  That incident can be seen here. 

Ron