Last summer I was able to see and photograph a juvenile Swainson’s Hawk expelling a pellet in the Centennial Valley of Montana. The young hawk, it’s sibling and one of the adults were in the area when this hawk flew onto a fence post close to the road.
One of the things I noticed first was how the back of the neck of the immature Swainson’s Hawk seemed enlarged, that is a pretty big bump.
Then the juvenile hawk bent over and repeatedly opened its bill, it was fairly obvious that the hawk was struggling. The lump seemed to move slightly forward with each attempt.
After several minutes the hawk expelled two rather large pellets, this frame shows the first pellet as it exits the hawk’s bill.
When the pellet expulsion was completed the juvenile Swainson’s lifted its wings, shook itself and flew off.
This is one of the pellets the hawk expelled, it consists of bones, fur and other undigested materials. Some folks might think this is gross, I see it as being as natural as this juvenile Swainson’s Hawk taking flight.