A spectrum activated
Summer is here — vibrant colors and intricate patterns are this season’s hottest trends, and we’re not talking about Couture Fashion Week in Paris. The fascinating process of molting in birds provides awe-inspiring results, which many would argue outshines anything Valentino can create. Natural scarlet reds, electric blues, sunny yellows, and emerald greens dominate the landscape, transforming the avian world into a living kaleidoscope.
Breeding season is often the most eagerly awaited event for birds and humans alike as bird plumage transforms, heralding a new era in the bird calendar. During the summer, many species of birds are still actively breeding, therefore nature continues to unveil spectacular transformations in certain species as they adorn themselves with these striking plumage changes.
Look in any bird guide book worth its weight or on any of the many ID apps out there, you should notice that some species will look different at certain stages of their lives and times of year. So how does this redesign happen?
Over the centuries various theories have been put forward, perhaps the most famous being when the Ancient Greek philosopher Empedocles proposed the theory of transmutation, suggesting that birds transformed into different species, shedding their feathers and becoming a different bird altogether. He was right about shedding their feathers, but nowadays we know that birds stay the same species as they simply go through a wardrobe refresh: they molt.
Feathers aren’t just pretty hats, jackets and trousers, they perform vital functions such as optimizing flight and providing insulation. As both the bird and the feathers age, periodically birds will replace all or most of their feathers during a molt, usually at least once a year. There are also those species who will undergo two molts as they change their plumage in and out of breeding season.
For many of us in the northern hemisphere, it’s hard to imagine the birds we see looking any different, yet the same can be said for people elsewhere in the world who see the same bird but in a totally different way, as a wintering bird rather than one ready to try for a new family. The Painted bunting, for example, undergoes one of the world’s most dramatic makeovers. These common songbirds breed in coastal south-east and south-central US states, and will have migrated from Central America, where they spend their winters as relatively inconspicuous birds with green plumage all over.
However, as the temperatures rise and they head north, they pass through Arizona and Mexico, known as transition states, where the males gradually lose these olive-colored feathers to showcase a phenomenal palette. Those lucky enough to have them visit their feeders can watch the males showcase their bright blue heads, green backs, and a mix of red, orange, and yellow on their underparts as they all vie for attention in the great mating game.
During the winter in Africa, India and southeast Asia, you can observe a plain grayish brown shorebird known as a ruff, where the males and females are hard to tell apart. But as winter fades and to escape the dangerously rising temperatures, these birds fly all the way across to Europe, undergoing their own dramatic plumage change as they head into breeding season.
The males display an elaborate assortment of colors, and it is here that we see where their name comes from: the flamboyant collar or ruff of ornamental feathers around their neck. Each male can exhibit different colors and patterns, ranging from black and white to chestnut and gold, making them very distinctive and appealing to potential mates.
Bad hair day
Right now in the northern latitudes of our planet, for those of us with feeders still up in our yards or with ample vegetation bursting with blooms, seeds and frequented by insects, we should still be seeing lots of birds around; at least when it’s not too hot during the day and they are yet to seek out the shade, just like us. As summer progresses, you should start to notice some bird species going through a molt.
This phase is also when a few of us get to glimpse something that can at first look a little concerning – bird ears. Our human ears are noticeable as they have an external structure, but bird ears lack this, essentially existing as a hole in the side of the head, below and a little behind the eyes. When the feathers on a bird’s head molt, these holes are exposed, and can have the unaware among us wondering if the poor bird has been injured or is afflicted by some disease; but it’s just their ears! You can relax, but thanks for looking out for them and asking if they are OK.
Most of us associate breeding season with Spring but Summer keeps the volume up, highlighting those beautiful and diverse plumage colors. What better way to enjoy the long sunny days than witness the beautiful Tyndall blue of the sky, the pulsing life force of the chlorophyll green and there, flitting through the branches and among the flowers, the wonderfully varied hues of so many beautiful feathers.