Bird feathers, colours and their arrangements are always intriguing. If one has been to the tropics, the variety is even more impressive. But I don't want to sell our local birds short: they are amazing in their own right.
Birds with crests are noteworthy. For some species the crest seems to be an important part of their courtship and display, which is obviously important for the species survival. This includes some species of waterfowl such as male Red-breasted Merganser and Hooded Merganser, where the fully displayed crest is most prevalent during the pair bonding period.
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| Red-breasted Merganser |
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| Hooded Merganser |
For so many other species of birds, the purpose of the crest seems to be less obvious, but undoubtedly has some role. Some of the most likely crested birds to be encountered in southern Ontario include the following.
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| Belted Kingfisher |
The crests of Cedar Waxwing and Northern Cardinal vary from time to time. Sometimes they are almost flattened, and other times they are quite erect. When a Northern Cardinal wants to be less visible, something that is hard for a bright red bird, its crest is almost invisible.
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| Cedar Waxwing |
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| Northern Cardinal |
The crest of the Pileated Woodpecker will vary a bit also, but often is quite upright.
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| Pileated Woodpecker |
It seems that the crest of a Tufted Titmouse is invariably quite noticeable and seldom lowered.
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| Tufted Titmouse |
The crest of a Blue Jay is often upright, but then this species often seems to be excited and vocal, except around their nests. Anywhere around the nest site, they will be very silent and furtive. I have had a pair nest in a tree in our front yard on occasion, and they went unnoticed for several weeks, which is surprising given how raucous and vocal they usually are.
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| Blue Jay |
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This leads me to discuss another fact about bird feathers. There are a couple of ways that colours appear. One is via the actual pigment in the feathers, and the Northern Cardinal is an example. However most birds that are blue, and some that are green, are not the result of either a blue or green pigment. It is the result of the refraction or bending of light rays passing through microscopic structures of the feather's melanin which is unique to the species. This filters out certain wavelengths, allowing certain colours to come through. Hence the colour of a Blue Jay's feathers, as well as other blue birds such as the Indigo Bunting, is the result of this light refractive process, not the pigmentation.
On a completely different 'birdy' note: Here is the bird of the day.
Happy Thanksgiving to any readers from the USA!
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