The great egret (Ardea alba) is a beautiful, large waterbird in the heron family Ardeidae. During breeding season, the great egret develops brilliant white plumage and long ornamental feathers on its back that distinguish its appearance from the rest of the year. Understanding the great egret’s breeding plumage helps birdwatchers identify it during courtship and provides clues about its behavior and ecology. Let’s explore the details about the plumage of the great egret in breeding season below.
Breeding Plumage
In breeding season, the great egret develops distinctive breeding plumage as follows:
Bright White Feathers
The great egret’s feathers turn snowy white, giving the bird its striking breeding appearance. The white feathers develop on the body, wings, and head. This differs noticeably from the nonbreeding plumage which shows some gray on the head and neck.
Long Filoplumes
The great egret grows long, thin, and wispy back plumes up to 30 cm long. Ornithologists call these specialized feathers “aigrettes” or “filoplumes.” There are normally 2 or 3 of these plumes extending from between the shoulders.
Decorative Back Plumes
In addition to the filoplumes, the great egret develops additional long plumes from the back, breast, and shoulders. These plumes can reach 20 cm long and have decorative curling at the tips.
Long Neck Plumes
The nape area at the back of the great egret’s neck is adorned with long lanceolate plumes up to 15 cm long. These blow gracefully in the wind when the egret is displaying.
Bushy Head Plumes
The great egret grows showy plumes on the crown and back of the head. These plumes stick out to create a bushy, full appearance.
Bright Yellow Feet
The great egret’s feet turn bright yellow in breeding plumage, contrasting against its bold white feathers. The yellow feet and pink-orange bill also intensify in color.
When Does Breeding Plumage Develop?
The great egret acquires its breeding plumage each spring by molting old worn feathers and growing in new feathers suited for breeding. The process takes around 6 weeks to fully complete.
By late March or April, the great egret will be adorned in full magnificent breeding plumage in time for courtship rituals. Breeding plumage is then retained through late summer while nesting and raising young.
After this, the great egret will molt again in late summer, shedding the long specialized feathers. Its appearance will return to nonbreeding plumage in fall and winter.
Why Does Breeding Plumage Develop?
The great egret’s elaborate breeding plumage serves several important functions:
Attracting a Mate
The showy plumes and bright colors help the great egret catch the eye of a suitable mate. The striking appearance signals fitness and health to potential partners.
Courtship Displays
The great egret uses its decorative plumes during breeding displays. It arches its neck, spreads its plumes, and extends its bill skyward in a graceful and visually impressive courtship ritual.
Signaling Territory
The conspicuous plumage advertises that the egret is prepared to establish and defend a prime nesting territory. Its bold appearance warns competing egrets away.
Camouflage and Shade
The white feathers help camouflage the egret in open wetland nesting areas. The head plumes also shield the egret and its young from sun exposure.
Unique Adaptations
The great egret’s breeding plumage has some special physical adaptations:
Powder Down
The great egret has fine “powder down” feathers that continuously disintegrate into a white powder. This powder helps maintain the clean, bright white appearance.
Green Skin
There is a greenish “skin wash” on the great egret’s head that contrasts sharply with its bill color. This enhances the visual display.
Iridescence
The feathers have microscopic structures that refract light and create subtle iridescent glows. This adds brilliance when displaying in sunlight.
Regrowth Capabilities
If feathers are damaged or lost, the great egret can fully regrow them in time for breeding season. Plucked feathers take around 5 weeks to regrow thanks to rapid feather growth cycles. This allows the great egret to always put its best feathers forward.
Historical Significance
In past centuries, the great egret’s breeding plumage made it a target for plume hunters who sought its feathers to decorate ladies’ hats. These decorative plumes were referred to as “osprey” feathers in the millinery trade.
Great egrets were hunted extensively in the late 1800s/early 1900s, with millions killed for their plumes. Conservation efforts ultimately put a stop to this practice, and great egret populations recovered after receiving protection.
Conclusion
The great egret’s elegant white breeding plumage plays an integral role in its breeding biology and behavior. The showy feathers enable courtship displays, signal fitness, attract mates, define territories, and camouflage nests. Understanding the details of this seasonal plumage helps provide insights into the ecology and natural history of these stately wetland birds. So next time you see a great egret adorned in its finery, take a moment to appreciate the beauty and function of its breeding attire.
