Why Feathers are Curved. Part one.

floating goose body feather

Why the shaft of feathers are curved. Part one. 

Most feathers have some curve to their shafts.  One of the reasons is for warmth.  A front to back bend on a body feather serves to control a bird's temperature. 

Feather curves are the main reason I use shadowboxes rather than trying to make the feathers lie flat.  I want to honor their natural shapes.

The most consistently and intensely curved feathers I know of are the body feathers from waterfowl.  Many of the body feathers on a swan are so inwardly curved that it takes only two to make a complete circle.  On most birds, the curve allows a larger air space between the body and the elements.  It’s like the wider the insulation is in your house or the thicker the layers of your clothing is, the warmer you are.  A neat thing about birds though is they can control how thick the air layer is.  Through muscle-feather control they can flatten the flexible shafts, pushing them next to their body.  Or they can fluff themselves by letting their feathers naturally curl to their max like you see songbirds do on a cold winter day.  I wish I could do that with my clothes.

Swans and their Feathers

Swan Feather cutouts  --mute swan

Someone actually counted every feather on a swan and came to the conclusion that they have more feathers than any other bird on earth.  I’m not sure that is true although it is the generally accepted or at least most widely quoted figure:  24,000.  Take the numerous outer feathers away on a bird like this and you have essentially a  long underwear-like layer of soft down feathers.

Everyone knows a swan is all white.  The all-white swan is beautiful and often triggers notions of the meaning of white, like purity and angels.  But white feathers are weaker and less durable than black ones.  Why? It has to do with the protein melanin, the same stuff that makes light-skinned people tan and gives some people freckles.  Melanin in feathers strengthens them against wear and also makes them black or reddish brown.  Many large birds need their primary flight feathers to last a long time.  A lot of mostly-white birds have black feathers where they need the strength and durability—in the flight feathers. White pelicans, snow geese,, white stork, wood stork, and many seagulls are mostly white except for their primary flight feathers.   

So then why is the Black Swan from Australia is all black except the tips of the wings white?  I don’t know for sure but assume that it’s because swans just keep their wings folded in when they feed, so except for flying, they don’t have to worry as much as other birds about wear and tear on their wing feathers.

I have been working a little with Martha Jordan of the Trumpeter Swan Society whose work includes rehabilitating, protecting, and reintroducing Tundra Swans.