Chickens waterproof feathers with an oil gland

After a drizzly day
just wet enough to damp their feathers but not so hard that our
chickens retreated to the coop, I dropped by the pasture and saw
every single bird preening.  If you’ve ever processed your
own birds for the table, you’ve probably cut out the oil gland
(more formally, the uropygial gland) on top of their tails, but
did you realize the gland’s purpose?  Like other birds,
chickens use the oil from this gland to waterproof their feathers,
which is just what my
flock was up to.  Each hen would run her beak over the oil
gland to load it up, then passed the laden beak over feathers on
other parts of her body, just like you might squirt some
moisturizer onto your fingers then massage that lotion into dry
skin.



Although preening is
essential in keeping feathers clean and dry (with the bonus of
making your birds look shiny and beautiful), a chicken’s preening
behavior also seems to have several other purposes.  One
study showed that scents within the oil emitted by a hen’s
uropygial gland attract the rooster and make him more prone to
mate with her.  For some birds, the gland’s oils contain a precursor of
vitamin D, which is spread on the feathers where it can be exposed
to sunlight and form the important vitamin.  Finally, preen
oil seems to back up dust
bathing as a way of keeping skin parasites at bay.



I’m always amazed by
how much I can learn about our flock by just sitting and watching
for a minute.  Chickens definitely give us more than just
their eggs!