Color. It’s around us every day from the green grass to the rufus orange-bellied Robins flying around this time of year. Have you ever truly stopped to wonder why our birds have evolved such bright plumage? Why are quaker parrots naturally green and bluejays truly blue? (Spoiler alert, they aren't!) I could go on for hours about the many different ways our birds get the colors they do, but I will just highlight a few of the most common here!
Pigments: Let's start with the most common. Just like in our plants, pigments are the primary reason we have such colorful birds. There are three structures of pigment in bird feathers: carotenoids (bright reds, yellows, and oranges), melanins (black, browns, rufus reds, and dull yellows), and porphyrins (an amino acid based pigment that produces bright colorations that glow red under a UV-light). Of course there can also be the absence of pigments that create white spots or albinism.
Structure: Instead of having true pigment in the feather some feathers have a different structure that simply refract light in a way that our eyes read it as different colors. Have you ever noticed how a starling has iridescent feathers that change from black to blue as it moves? Or the throat of a hummingbird that can miraculously change from red to purple with the turn of its head? That is because there are little feather barbules reflecting light and with each small movement the light changes where it’s hitting that barbule, therefore tricking our eyes into seeing different colors. Non-iridescent feather structures are where we get our blue birds from! True blue birds are actually a dull gray in color, but the structure of the feather reflects as blue. Next time you’re out, try to spot a blue jay on a cloudy day, you’ll notice it’s not truly blue after all. If you dip Sadie, our Hyacinth macaw’s feather into water it will change from blue to a dark gray/black because the light is now reflecting differently off of the feather.
Diet: I think the most known species here is flamingos. Going back to carotenoids (bright red, orange, and yellow) you may wonder how those even come to be in the first place. In order to build carotenoid pigment either food, fungus, or bacteria need to become involved to allow the feather to photosynthesize the colors. The red krill enhances the pink in flamingos and carrots can help red factor canaries become brighter. Sometimes the brightness of a bird can be a wonderful determining factor when it comes to the overall health of the bird. Male Eclectus are known for having bright candy corn-like beaks, but if they have a poor diet that color quickly dulls and fades to a pastel.
Breeding Plumage: Now if we put it all together it can help give us the WHY to it all. Knowing that the health of the bird can influence how bright it is can tell us why that male birds tend to get the vibrant breeding plumage over the females. They’re showing off their health, their ability to search for food, and most importantly their great genetics. When female birds are looking for a mate they will look at the feather quality and brightness to see who the healthier male is.
Protection: Have you ever wondered why female birds tend to look more drab and dull? Or why green tends to be the most common parrot coloration? The short and sweet answer is the closer you look to your environment the better protection you have from predators. Wild species of female birds tend to sit in brown nests, on brown trees or in brown nesting cavities which is why they tend to have the dull, lackluster (respectfully speaking) appearance. Males fight for territory and dominance and therefore have brighter colors to prove they’re the stuff, but to also guide predators away from the nesting areas with their bright and flashy colors. Cockatiels are naturally more grayish as they tend to be grassland birds and it helps them blend into the grass.
Now of course there is a TON more information to learn about the who, what, when, where, and whys of bird colorations, but this pretty much sums up the surface level information of all that is bird feathers.
