I’m pretty sure that both of my mallard hens are incubating a full clutch of eggs now. I can peek at Honey’s nest when she comes down to the pond once every day or two for a drink and a feed, but Dorothy’s nest is on a ledge in front of a window that cannot be accessed. It’s important to be able to look at the nests, for we’re never sure when hatching takes place unless we can see the ducklings and thus be prepared to take care of them and their mom. (They jump off the ledge to the pond within 24 hours after hatching.)
Today when Honey was on the pond (in fact, when I was writing the previous post), I ran to the next building, went up to the third floor, and, pulled back the cardboard on the window that gives Honey privacy. You see a photograph of her nest below. It’s hard to take a good photo through a screen with a point-and-shoot autofocus camera, but you can see her rough saucer of twigs that she’s lined with down from her breast. (I find it ineffably touching that mallards pull out their own feathers to help cushion and insulate the nest.) Only one pastel-green egg was visible, but since there were three eggs over a week ago the rest must be buried in the down. Clutch size is usually 8-12 eggs.
I’ve circled the one visible egg: a future duckling. Look at all that down!
I looked at the picture of the nest first, and thought all that down was actually chicks!
Does the mallard (bird, generally ; avian dinosaur, more generally) do anything to make the feathers more pluckable at nesting time? I’m thinking about modification to whatever the widespread physiology behind seasonal moulting is, but maybe locally expressed (breast only) or at a different time (do mallards have a specific season for moulting?) to normal?
Does the moulting physiology produce any visible changes in the feather root? The sort of change that might potentially be identified in the fossil record? There was a case a good few years back when the recovery of a proteinaceous “soft tissue” was reported from a T.rex (I think “Sue”, but I wouldn’t go to the gallows over that), and a frequently-missed point of the work was that the osteology identified “spongy medullary bone” which is a calcium accumulation and release mechanism for support of laying eggs, and therefore strong evidence that the dinosaur specimen was of a female.
Oh, there is a “Dinosaur Soft Tissue Research Institute”, https://dstri.org – didn’t know about them previously. They have goodies, for dinosaur fans of a certain age.
I repeat my question from last week – why do the eggs not die left un-incubated? How low a temperature can they tolerate & for how long?
Are commercial duck eggs unfertilised? In other words if I bought some fresh & incubated them could I get ducklings?
He said eagerly! 😊
It’s possible, but the odds are against it: https://www.bbc.co.uk/news/uk-england-beds-bucks-herts-52838747
I don’t know, Dom. I suspect they remain in a state of stasis for a while after being laid, but then eventually go bad. I have no idea how low temperatures they can tolerate. My understanding is that nearly all duck and chicken eggs sold are unfertilized. If you did incubate a fertilized egg, however, you have to know exactly what you’re doing, with a professional incubator, humidity, turning eggs, etc.
“I find it ineffably touching that mallards pull out their own feathers to help cushion and insulate the nest.”
And I find it ineffably sweet that you “ran to the next building, went up to the third floor, and, pulled back the cardboard on the window” so you could take a peek at Honey’s nest, without disturbing her.
Thy bosom is endeared with all hearts, as the Bard said in Sonnet 31.
Are their eggs the size of a chicken’s? They look to be a little larger.
I didn’t compare them, but I’m told that they’re slightly larger than chicken eggs and also shaped differently (not as pointed).
“[A]nd also shaped differently (not as pointed)” – it sounds like miniature duck eggs could have ended the strife in Lilliput between the Big-Endians and Little-Endians.
You bring up an interesting point. Why round (like many turtle species) or “rounder” than pointed? Obvious reason is it would be easier to lay an oblong egg. But the round eggs still exist. Perhaps oblong has a risk of blocking a tube? Biology is a tough nut.