Barn Owl pellet analysis

Owl pellet facts & video: Find out all about Barn Owl pellet dissection and how to analyse the contents.

What are Barn Owl pellets?

  • Owl Pellet: Barn Owl PelletingBarn Owls are unable to digest the fur and bone of their prey, which they usually swallow whole.
  • The indigestible parts are regurgitated (coughed up through the beak) in the form of an owl pellet.
  • After feeding, producing a pellet takes 6 hours or more.
  • After each night’s hunting an owl regurgitates 1 or 2 pellets.
  • Barn Owl pellets are typically about the size of a man’s thumb and black when fresh.
  • Pellets often contain the remains of 4 or 5 small mammals.
  • Pellet dissection can tell you exactly what an owl has eaten. 

What is a Barn Owl pellet? – a 4 minute video with David Ramsden from the Barn Owl Trust.

Where to find Barn Owl pellets

Pellets often accumulate at roosting or nesting sites, where owls can hide away and shelter from the weather. There are several signs of Barn Owl occupation to look out for, which help decide if the pellets are from Barn Owls or from a different bird.
Take care if collecting pellets from the wild as Barn Owls are a protected species and it is illegal to disturb them while breeding. However, it’s likely that any owl nest is high above you and if you are quietly collecting pellets on the ground you are probably not going to disturb the owls.

Bird pellet identity chart: Identify the bird pellets you find. Most birds produce pellets, which look different according to what they eat. Barn Owl pellets are black when fresh and dark grey when dry.

Owl pellet storage and preparation

Fresh owl pellets can be dried or frozen, and kept in an airtight container. If moist pellets are stored together they can become a congealed mass of pellet debris. If pellets are stored in a sealed container a number of grubs or small moths may be found once the container is reopened. These are clothes moths and their grubs are completely harmless (except to wool).

Barn Owl Pellet age guide chart

Barn Owl pellet age chart

Barn Owl pellet analysis

In dry well-used roost sites lots of Barn Owl pellets can accumulate. Using our owl pellet age guide photo on the right, it’s possible to work out how long Barn Owls have been using the site and how recently the owl was present.

Barn Owl pellets break down with age as clothes moths eat the fur, leaving the tiny bones behind, which can last for many years.

Barn Owl pellet dissection

Pellets can be analysed wet or dry. It is easier to analyse dry pellets, but to extract all of the small mammal bones intact, dried pellets can be soaked in water for 24 hours.

Gently tease the pellet apart using your fingers or tweezers. Although pellets do not smell, (they are not faeces) hands should be washed thoroughly with soap and water after this activity.

Field Vole Skull Top

Photos of bone identification for owl pellet analysis.

Barn Owl pellet contents identification

Many thousands of Barn Owl pellets have been analysed so we know a great deal about what Barn Owl’s hunt and eat.

Wild Barn Owls eat mainly small mammals such as voles, shrews and mice. Other less common items include rats, birds and frogs.

The simplest way to identify which small mammals have been eaten is to search for the lower jaw bones, then ‘pair up’ the right and left jaws from each pellet.

Science Barn Owl Pellets

Barn Owl pellet analysis and dissection for schools – free* PDF to download

The shapes of the bones, particularly the jawbones, can tell you what species of animal the owl has eaten. You can also count how many prey items are contained within an individual pellet.

Take a look at a our photos of owl pellet analysis to help you to identify bones

Barn Owl pellet analysis and dissection for schools – free* PDF to download. Includes owl pellet analysis diagrams.
*Free for personal and educational use only – copyright Barn Owl Trust.

Barn Owl Trust Owl Pellet Dissection Pack

Contains everything you need for owl pellet dissection – including a real Barn Owl pellet! Natural science straight from the owl’s mouth! Owl pellet analysis is a fascinating activity for adults and children. You can buy the packs from our online shop.

Barn Owl Trust Pellet Dissection Pack Front Cover     Barn Owl Trust Pellet Dissection Pack Contents

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