Why Do Birds Preen?

Imagine thousands of small, fragile fans on the surface of your entire body. Now suppose you didn't have any hands to fix them, only your mouth. That's the life of all birds. That is why your budgie or parrot spends so much time picking at its feathers.

However, why do birds preen so much? Is it just a clean up or more? This is the easy answer and what this habit reveals about your pet.

A bird preens by pulling feathers through its beak, one at a time, starting from the base of the feather to its tip. It can also nibble along a feather with the tip of its beak. It may seem fussy but there is a reason behind each move. Birds scratch their head with their feet as the beak cannot reach.

A feather is not a single piece of solid material. It consists of numerous thin branches. Tiny hooks are found on these branches which lock together, similar to a zip. The locked surface maintains the strength and smoothness of the feather.

Flying and daily wear pull these hooks apart. Preening "zips" them up again. Without preening, the feathers would turn ragged and be less efficient in keeping warm and flying.

According to Audubon, many birds spend more than 10 percent of their waking hours preening.

The preen gland or uropygial gland is a small gland located near the base of the tail of most birds. It produces an oily substance. The bird squeezes a bit of oil onto its beak, then spreads it across the feathers as it preens itself.

This oil helps to keep feathers flexible, so they don't become dry and brittle. It may also slow the growth of certain bacteria and fungi. Many believe that it is the oil that causes the waterproofing property of feathers. Actually, a lot of the water resistance of a feather comes from its structure. The oil helps protect that structure over time.

Here's a fun twist. The preen gland is not present in some parrot species, but they still preen. That demonstrates that spreading of oil isn't the only reason for preening.

Preening also helps to get rid of dust and small parasites, including feather lice. Research on pigeons found that the ones that had lice on them spent more time preening. The additional preening ended when the lice were removed. So the habit is an inbuilt defence which is called into action when necessary.

The process of replacing feathers in birds is called moulting. A newly growing feather is enclosed in a waxy sheath, often called a pin feather. As it grows, the sheath has to come off.

Your bird will nibble these sheaths away as it preens. It is for this reason that you may see little white flakes around the cage when moulting. It's normal.

Have you observed two lovebirds or budgies gently nibbling each other's heads? This is called allopreening, which simply means preening another bird.

It has some valuable functions:

The Association of Avian Veterinarians notes that allopreening has been seen in more than 40 bird families.

Pet parrots often treat their humans like flock members. A bird may put its head down and fluff the feathers on its neck in front of you. Well, that's an invitation to scratch its head.

Some birds take it further and "preen" your hair, eyebrows or even a scab. It's a sign of trust. Be gentle and stop if it pulls away.

Feathers are kept neat when they are preened normally. Over-preening is different. You may notice:

Over-preening can be linked to stress, boredom, dry skin or parasites. Even hand lotion on your skin may leave residue that a bird keeps trying to clean off. Birds also sometimes preen when torn between two urges, which is a sign of inner conflict.

Visit an avian vet first if you notice feather damage, to rule out illness. Then consider the bird's routine, toys, company and bathing.

So, why do birds preen? To keep their feathers zipped, oiled, clean and ready for flight. They also preen to manage their new feathers and to bond with the birds, and people, they love. A healthy bird is a bird that preens healthily. When feathers are damaged, it's time to take a closer look.