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The Daily Bucket is a nature refuge. We amicably discuss animals, weather, climate, soil, plants, waters and note life’s patterns.
We invite you to note what you are seeing around you in your own part of the world, and to share your observations in the comments below.
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November 27, 2018
Salish Sea, Pacific Northwest
Buffies are abundant in my local bays now. What’s not so common is sunshine, here in the soggy Northwest. A buffie in sunlight is even more spectacular than usual, the drakes especially. Without direct sunlight, buffies are in black and white.
Here’s a guy paddling perkily along as they do.
When he turns to catch the sun, his iridescence really dazzles. Only his head plumage is colorful though, his back feathers are a glossy deep black.
But it gets even better…wowza! The colors.…
Behold the beauteous buffie —
That iridescence is structural color not pigment, which is why it varies. From Cornell Ornithology:
Iridescent colors are the result of the refraction of incident light caused by the microscopic structure of the feather barbules. The refraction works like a prism, splitting the light into rich, component colors. As the viewing angle changes, the refracted light becomes visible in a glowing, shimmering iridescent display.
But there’s something else going on here. There’s a clue this fella is about to dive, which he needs to do quite frequently for food, being a small duck living in cold water. Tiny: buffies are a third the size of a mallard! Small warm-blooded creatures lose heat faster than large ones since they have greater surface area relative to their volume (this is the reason there are no marine mice, just too much surface to lose heat from, not enough “insides” to produce and store heat). Buffies need food to generate heat, and that means hunting for crabs and clams on the shallow bottom. Buffies spend a lot of time hunting:
Foraging is the chief daytime activity. During the day, more time is spent foraging in winter than in summer. At night, birds continue to forage in winter, but are generally inactive in summer. Birds may be forced to feed at night in winter because short daylength may not provide enough foraging time to meet the daily energy requirement of this small species. The low proportion of time spent in interdive pauses and sleeping during the day in winter supports this interpretation. This suggests that diving for small invertebrates is an expensive foraging mode for a small duck.
- Buffleheads. Birds of North America birdsna.org/...
How do I know this buffie is about to dive? Take a look at the shape of his head. See how it’s flattening down? Diving ducks are able to compress the air out from between their feathers so they aren’t so buoyant, making it easier to swim to the bottom. Just long enough to dive though. Puffed up feathers are better insulation in general. And having a big buffalo-shaped head may be a fine look for a bufflehead.
Ready....
...dive!
All these pictures are of the same duck, one moment after the next. Can you guess what stage the title photo is in this sequence — between which of these 5 preceding pics does it belong?
Even squeezing air out of their feathers these little ducks are still extremely buoyant. Once they’ve caught their prey, they just stop swimming, and bob back up to the surface.
Caught him just surfacing. Looks like he’s crunching a crab or something.
🦀
Overcast and sprinkly in the Pacific Northwest. No iridescence today. But buffies!
Edit @ 8:30am: seeing some thinning of the overcast. Possible sunbreaks later???
What’s up in nature in your area today?
🐙
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