(noun) A prominent tuft of feathers on the crown of a bird's head.
Types of Crests
The size, shape, color, length and thickness of crests can vary greatly. Some birds have just a very small and subtle crest, such as the ruby-crowned kinglet, while others have longer, thicker, more prominent crests like the northern cardinal or blue jay. In some species, such as the double-crested cormorant, a pair of crests are located on the sides of the head rather than directly on the crown. Some crests are very thin and may only be a few feathers, such as the wobbly crest of the California quail. When a crest is exceptionally prominent, it is a distinguished field mark and may be part of the bird's name, such as the sulfur-crested cockatoo or crested tit.
Most birds show crests year-round, but in other species, it is part of their breeding plumage, and it will disappear after the breeding season as the bird molts.
Some birds have features that may appear similar to crests, but are actually very different in structure and composition. The most common crest-like features include:
- Comb: A fleshy, upright structure on a bird's head. The size, shape and color of combs can vary, but they are all fleshy growths and are restricted to just the top of a bird's head. The red junglefowl and domestic roosters all have combs.
- Casque: A hard growth on the head, composed of keratin. Casque size and shape also varies, and these structures may show scratches, chips or other wear over time. All cassowary species show casques.
- Wattles: Fleshy growths that vary in size, shape and color on a bird's head, face and neck. Wattles on the head may seem similar to crests, but are not confined to the top of the head. Muscovy ducks and wild turkeys show extensive wattles.
How Birds Use Crests
Birds are often able to control their crests, and crest position can be an indication of a bird's emotions or stress. Birds may raise or lower a crest for a courtship display or to show aggression, dominance or submission. The stronger the movements of the crest, the stronger the emotions that cause the action.
Crests as Identification Field Marks
A crest can be a useful field mark for birders. When using a crest for bird identification, note the color, shape and length of the crest, as well as its thickness and whether it appears to be just a few feathers or the full crown. Also note how the bird uses the crest and what positions the crest has in a bird's relaxed posture versus more aggressive or prominent displays. In some species, the crest is so significant and prominent that it can be a diagnostic field mark, such as the large, colorful crest of the male wood duck.