How Are Owl Pellets Formed?

Barn owl

Owl pellets are the indigestible parts of an owl's meal that the bird regurgitates. Owl pellets, typically composed of things like fur, bones and feathers and found on the ground where the owl nests or roosts, form in the bird's digestive tract.

Eating

The owl will capture other birds, small mammals and other prey before ripping them apart with its sharp beak and swallowing chunks of its victim.

Separation

The chunks of an animal make their way down the esophagus into an organ called the proventriculus, which secretes a series of digestive juices onto the food. Then this mass moves to the gizzard, which separates that which the owl can digest from that which it cannot.

Pellet Forms

The digestible portion of the meal goes through the bird's digestive tract while the rest forms into a round pellet. This pellet moves back up into the proventriculus where it will stay for many hours.

Regurgitation

Before the bird can eat once more, it must regurgitate the pellet. The owl appears in great discomfort and seems like it cannot breathe during this process, but once the pellet is out the bird is back to normal.

Significance

People who discover these dried pellets can tear them apart and get some idea of what the bird has had on its menu. The pellets also give away the presence of an owl's nest or roost.

References

• Kidswing.com: How do Pellets Form?