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Hello friends, Hallie here from Petit Manan Island!

Life here on Petit Manan is going so well. Our tern chicks are hatched and getting close to fledging, our pufflings are fluffier and plumper than ever, and we even have our first black guillemot and razorbill chicks.

One of the cool things about working on such a small island like this is when you have a new avian visitor, you notice. We are up to 110 bird species recorded on Petit Manan Island this season, which is remarkable in itself. We have had everything from warblers to short-billed dowitchers to even a least bittern, a small bird that you typically find in marshlands on the mainland. And as well, we have had a lot of birds with interesting plumage show up to the island — like this Common Murre.

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Leucistic Common Murre next to Razorbill and Atlantic Puffin

Common Murres are usually a dark chocolate brown, which is produced by melanin. This bird,  however, is silvery-grey — a result of a genetic mutation that inhibits melanin production. This result is called leucism, which is similar, yet very different to albinism. Regardless, it makes up for a stunning result — this bird very well may be one of the more beautiful I have ever seen. Whether or not male or female common murres also think so is up for debate — hopefully this bird’s unique plumage will not inhibit it from procreating in the future.

Melanin is one of many ways birds color themselves. The laughing gulls here use melanin to create that dark mask during the breeding season, which they use to deter other laughing gulls from their nests. You also often see birds with darkened wing-tips, like the terns, in which the melanin is used to strengthen the feathers and make them more durable.

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Adult Atlantic Puffin showing the orange-red carotenoid coloration in the bill and eye

But what other colors do we see here on PMI that have significance in birds?  Since we have been catching puffins this last week, I have been captivated by the bright orange feet and bills that the puffins display during the breeding season.  Puffins, and many other birds, get this rich orange-red color from carotenoids — a color they metabolize directly from their food. Puffins use the intensity of this color to show potential mates and rivals how fit they may be. The brighter their bills and feet, the better at fishing and raising a chick they may be! You can also see melanin in the feet and the mouths of black guillemots!

Next time you see a color in a bird, its worth asking exactly why it is that way. Often even the most subtle of colors on a bird have such an immense meaning. I will be doing the same — sitting here wondering why we get tern chicks in two different colors. Any ideas?

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Common Tern chicks from the same nest showing the two different plumage colorations

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