Bird crests are feather formations found on the heads of certain bird species. Crests can take many different shapes and serve a variety of purposes for birds. In this article, we’ll take a closer look at what bird crests are, the different types of crests, and the various functions they can serve.
What are bird crests?
A bird crest refers to a grouping or tuft of feathers on a bird’s head that sits above the eyes. Crests are formed by elongated feathers growing off the crown of the head. The feathers stand vertically erectile, meaning they can be raised or lowered at the bird’s will. When raised, the crest appears as a prominent feathered crown on top of the head.
Crests are found in a number of bird families, including parrots, cockatoos, cuckoos, bird-of-paradise, and grackles. The shape, size, color, and position of the crest can vary significantly between species. Crests themselves are composed of feathers called plumulaceous feathers that have a plume-like or fluffy texture to them.
Types of bird crests
There are a few main types of crest configurations found in birds:
- Fan-shaped crest – Spread wide across the top and rear of the head. Seen in cockatoos.
- Erectile crest – A narrow crest of feathers that runs from front to back on the head and can be raised upwards. Seen in parrots.
- Powder-puff crest – A dense circular crest that appears powdered. Seen in certain cuckoos.
- Ribbon-like crest – A long, slender crest extending horizontally off the back of the head. Seen in some birds-of-paradise.
The variation in crest types is suitable for the different signaling purposes crests can serve, which we’ll explore next.
Functions of bird crests
Bird crests serve a variety of functions:
Visual signaling
One of the primary purposes of crests is visual signaling. When a crest is erected, it creates a striking visual marker that stands out prominently. This can serve several signaling functions:
- Species identification – The unique shape of a crest can help birds identify others of their own species.
- Mate attraction – Colorful, prominent crests help attract mates.
- Territory defense – An erect crest may signal an intent to defend a territory from intruders.
- Alarm signal – Rapidly raising the crest can signal alarm or preparation to flee.
- Mood display – Crest position can help communicate mood or status.
By dynamically manipulating their crests, birds can create conspicuous changing visual patterns for communication.
Sound production
Some crests play a role in sound production and vocal signaling. In certain bird-of-paradise species, the specialized ribbon-like crest forms part of a resonant system that amplifies courtship calls. The thin feathers vibrate to create a unique sound.
Mate assessment
During courtship, crests play an important role in mate assessment. Prominent, colorful crests signal fitness and can help attract a mate. The size, symmetry, and display performance of the crest offers females information on the quality of potential mates.
Neck protection
In some species, the crest may also offer protection to the back of the neck, shielding it from sun exposure. Having elongated crest feathers helps protect the bare skin on the nape which is more vulnerable to drying out and sunburn.
Why do only certain species have crests?
There are a few leading theories as to why some bird groups evolved elaborate crest feathering while most birds lack crests entirely:
- Sexual selection – Crests evolved through mate choice and preference for more ornate plumage displays.
- Species identification – Crests help distinguish similar species that overlap in range and habitat.
- Forest-dwelling adaptation – Crests are more common in forest-dwelling birds where visual communication is more important in dense vegetation.
The prevalent theory is that crests arose predominantly due to sexual selection for more elaborate ornamentation to attract mates. However, they likely serve additional purposes like species identification as well in certain taxa.
Notable crested bird species
Some of the most iconic and easily recognized crested bird species include:
Cockatoos
Cockatoos are a family of crested parrots native to Australia and the south Pacific. They are well known for their fan-shaped crests which can be raised and lowered.
Palm cockatoo
The palm cockatoo has a very large, distinctive crest that can grow up to 10 inches long on males. Their crest makes up a third of their total body length.
Umbrella cockatoo
When displaying, the umbrella cockatoo can fully extend its crest feathers covering the whole head like an umbrella.
Gang-gang cockatoo
The gang-gang cockatoo has an erectile crest that leans forward giving it a unique “mop top” appearance.
Birds-of-paradise
Birds-of-paradise are most famous for their wildly elaborate plumes used in mating displays. Some species have specialized ribbon-like crests as well.
Twelve-wired bird-of-paradise
Male twelve-wired birds-of-paradise have strand-like yellow crest plumes that extend horizontally from the back of the head up to 8 inches long.
Lawes’s parotia
The Lawes’s parotia has an emerald green pointed crest used in its unique “ballerina dance” courtship routine.
Western crowned pigeon
This large ground pigeon has an elaborate fan-shaped lace-like crest of blue feathers, giving it a distinctive regal appearance.
Conclusion
In summary, crests serve numerous important functions for birds including communication, display, sound production, and neck protection. These specialized feather tufts arise mainly from preferences for ornamental traits and the evolutionary advantages they can provide. Crests allow birds to better signal their identity, mood, alarm, or fitness as a potential mate. Next time you see a feathered headdress on a bird, consider the unique purposes it may serve.
