tempus fugit

By ceridwen

Waste disposal

Of the owlish kind.
Continuing yesterday's garbology theme, I present the residue of a barn owl's dinner(s).

Having learnt that a local project is seeking to log the barn owl population in this area, I headed for the only site I know that hosts a member of the species Tyto alba. It's an old barn belonging to a former country estate. Sure enough as we entered there was the soft scuffle of wings as a pale shadow retreated into invisibility behind the roof structure. Missed it again! But at least I know it is still there - not that ample evidence was not visible at my feet. The floor beneath the owl's roosting place was littered with black turd-like objects which are the pellets an owl regurgitates before it eats again. They contain the indigestible matter from its last meal: the tiny bones, teeth and fur/feathers from the small rodents (voles mainly), rabbits, frogs and little birds which constitute its prey. (You may be able to identify some of these items among the broken-down pellet material if you magnify.)

Barn owls, those mystical and often feared birds of folklore and legend with their white faces, silent flight and eerie shrieks in the night, have greatly dwindled in numbers as farming practices have changed and barns have been lost or converted into holiday homes. Their food species are less populous too and, contrary to expectation, it is the availability of prey that controls the barn owls' numbers, and not vice versa.

Unlike most birds, owls don't possess a crop in which to break down the roughage in their diet so they have to eject it from their gullet in order to make way for the next meal. When an Owl is about to produce a pellet, it will take on a pained expression - the eyes are closed, the facial disc narrow, and the bird will be reluctant to fly. At the moment of expulsion, the neck is stretched up and forward, the beak is opened, and the pellet simply drops out without any retching or spitting movements. There's a clip here of a snowy owl regurgitating and yes, it does look a rather undignified business.

Owl pellets are popular as teaching aids for dissection and are even offered for sale on Amazon - currently out of stock so maybe there's a marketing opportunity for me there.

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