A recent rain after a dry spell gave me a glimpse into the life of birds that I had never quite seen before.

It had been at least a full week, if not more, without a drop of rain. I ran the sprinkler for my flower and vegetable gardens almost every day, as well as keeping the bird baths full and clean. I thought this would keep the birds more than happy. But they must have viewed this as a barely adequate sponge bath compared to what they did once the warm, steady rain began.

Suddenly, the air was filled with melodious song; it was as if I had just walked into an aviary – a wild aviary. The goldfinches and purple finches were singing their little hearts out, producing a wall of sound so joyful and alive it gave me goosebumps. And they were bathing and preening as if they had not done so in years.

The goldfinches splashed around in the growing puddles, fluffing their plumage, ducking their heads into the water, and fluttering their wings to ensure a thorough bath. Some of them stood in puddles belly deep, looking like little balls of floating fluff.

Funniest of all were the mourning doves. They perched in a row on the telephone pole wires. First one, then another, would list dangerously to one side, lift the opposite wing, and let the falling rain wash over their underwing feathers. They’d then close that wing, lean over, and lift the other wing, repeating the process. They were so intent on washing their “underarms,” they were comical. I imagined their apparent joy at taking a proper “shower” was akin to my relief in showering after several days of rustic camping.

Perhaps the rain held a special significance of which I was unaware. I had read, for instance, that in tropical areas the coming of seasonal rains signaled the beginning of breeding season for parrots. In this case, the author (Joanna Burger, “The Parrot Who Owns Me”) also observed the obvious excitement and increased vocalizations of wild parrots during a downpour. She saw the birds bathing enthusiastically, preening themselves and each other.

Basically, though, birds keep feathers clean to retain their insulative and water-repellant qualities, as well as ensure their proper function for flight. Water baths, dirt baths, even sun baths are important ways to maintain feathers and reduce populations of any parasites in residence.

The vanes of the feathers are held together by an intricate series of interlocking, and progressively smaller, barbs. Part of the bathing process involves preening, where the bird runs a feather lightly through its bill. In this way untidy or unraveling feathers are “zipped” back up.

Feathers can also become brittle with age and exposure. To prevent this, birds obtain an oily substance from a gland at the base of their tails. Containing waxes, fatty acids, fat, and water, this substance cleans and maintains a feather’s flexibility, waterproofing, and increasing its insulative properties. Certain lipids of this preen gland oil also repel fungi and bacteria that ingest keratin, which is the substance of feathers.

Interestingly, some feathers can also be used to carry water. Desert sandgrouse in Africa must often travel many miles between their nests and water holes. Once he soaks his modified belly feathers – the inside surface of which absorbs and holds water – the male of this species flies back to his young, and they drink the water by squeezing the wet feathers in their bills. Male sandgrouse can carry up to 40 milliliters of water in each trip.

The next time you see a bird bathing or preening, think of all the functions a feather must fulfill. They surely are one of nature’s miracles.

NEWS bird columnist Chris Corio can be reached at bdnsports@bangordailynews.net