hufflefluffles asked:

in the spring, there was a family of ducks around my uni's campus that had mostly standard yellow/black-mix ducklings, and one solely yellow duckling, which seems to have grown up into a mostly white duck (with some black/dark feathers) is it likely to be a leucistic duck? (I've been trying but failing to get a decent photo of it to tag you in)

elodieunderglass answered:

Ohhhh my days!!!!! How exciting !

Without looking at the duck it’s hard to say - but it might be a Manky Mallard.

With the exception of the Muscovy duck (the one with the weird face growths) all domestic ducks are derived from the wild Mallard. They can interbreed with each other, and they’re very social, so in areas with lots of domestic ducks, you’ll sometimes just see a white farmyard-style Peking duck swimming around with the wild Mallards. (People also “release” their unwanted pet ducks into the wild. I have Stories about why this is a terrible idea, including the fact that ducks practice a lot of dubcon and noncon, to put it gently.) finally, a “released” duckling, if it is lucky, might just be able to wangle its way into being adopted by wild parents.

So it’s not unusual for Manky Mallards to pop up, getting the birdwatchers all excited with their funky colours and patterns, before they find out that the duck in question is just a farmyard x wild cross.

Pure yellow ducklings absolutely do turn into white ducks, so the question is - is it a leucistic mallard, an albino or a farmyard descendant? And for that, I just don’t have an answer! I’d have to see the adult duck. By which I mean YES PLEASE SEND ME PICTURES I MUST ADD THEM TO THE HOARD.

But if we consider that white domestic ducks are originally derived from Mallards… are they not ALL a type of color morph, in themselves? Where does the leucistic wildtype color morph meet the domesticated color variant? Is it different for different species of animals, and why? That is our philosophical assignment to ponder for today.

[hufflefluffkins]

the ducks are very friendly to people eating lunch outside, so one of my friends managed to take this photo of them today in the sunshine

[ID: six brown ducks and one white duck, standing clustered together on grass. one brown duck is looking directly at the camera, the rest have their heads turned sideways. the white duck has its head bent towards the ground]

it seems to have the same kind of black pattern as the rest of its gang, but is white underneath while they’re brown. as they all appeared at same time and about the same size it seemed like an odd-one-out part of the family, rather than an Ugly Duckling(/Cygnet) situation

for comparison, some of the family of ducklings in May:

[ID: an adult female duck stands on a plank of wood into a pond, with a yellow duckling and a black/yellow mix duckling standing further down the wood at the edge of the water. there are two black/yellow ducklings in the water with their heads down]

(people were very excited about the Single Yellow Duckling, so quite a lot of photos were taken of it, but I haven’t seen as many of the White Duck)

[elodieunderglass]

Aaah!! Yes! 😍😍I think you’re right! that’s a leucistic male! See how his wing patches (usually iridescent violet/blue) are still dark? And how his head (usually iridescent green/black in a mature male) is dark, stopping abruptly where his white vicar collar would be? That’s a classic thing! Leucism is often “just like the wild color pattern but kinda bleached” and if you see faded color where the iridescence on a bird would go, it suggests the underlying pattern, and thus genetics, are wildtype. Like you say, if he has the same PATTERN, just with white colouring, then he’s more likely to be a morph than a manky!

In the first pic, it even looks like he has a dab of Mallard eye makeup, further suggesting that he has a dilute version of the colours his siblings have.

He’s immature in the second pic and so are his brothers in the front right - you can see they have dark heads with the color coming to an abrupt stop where the vicar collar will be. These dark heads will go iridescent in their breeding season and the rest of the male color pattern will develop. Females are also brown, but they don’t have this abrupt line. I think the one in the far back is a young lady. The gender of the individual on the far right is a mystery to me and I support that.

I take it all back…. I was skeptical since leucism is more unusual, and Manky Mallards are quite common… but I was a fool and an unbeliever!

Please thank and congratulate your friend! You are the heroes of my day!