Mule ducks: how do you spot them and sex them?

[Tatum hills]

I have hatched my first ever lot of ducklings last October and I know 2 of the 8 will be mules as their dad is a mallard breed (crested drake) and mum is a Muscovy. I was told it'd be obvious who the mules are but not to me Six of the ducklings now make a definite QUACK, but 2 are larger than the rest and make a funny noise which sounds more like a Muscovy than a drake to me. My questions are :
1. Do drakes take time to perfect their call like cockerels?
2. What sound and other features do mules have that may help me identify them?
3. If the mules don't quack, how do I sex them?

 

[sourland]

Can you post pictures? If they are 'Quacking', they are not pure muscovies.

 

[Buck Oakes]

True and also ducks esp Muscovies can have offspring from different fathers so if u do have a Muscovy male as well then some babies could be pure bred Muscovies.

 

[Buck Oakes]

Also it's hard for mules to actually be bred, only some percent of eggs are actually fertilized, I think 60% but then more are lost because they're anatomy doesn't match the Muscovy hens eggs size, or the offspring are to frail and can't even hatch so if u got a good portion of mules then great

 

[Tatum hills]

Thanks for your replies but there seems to be some confusion. I don't have a Muscovy drake, so I know none are pure muscovies but my question is: do the Muscovy x mallard quack or not? And if not how to you sex them? I know mules are sterile which is why I am trying to work out who's who as I don't want to sell a mule to a breeding home.

 

[Buck Oakes]

Well if u only had babies from her and that male then all are mules

 

[Buck Oakes]

And I think it's a mallard derived male to Muscovy female that makes hinnies, I'm not sure, hinnies are primarily female and lay eggs with early any being fertile but there have been cases where some have had offspring with a Muscovy male.

If I'm wrong then they are mules who r primarily male

 

[Buck Oakes]

Not saying u can't get male hinnies bc u can

 

[sourland]

All are hinnies/mules and even if they lay eggs, they will not be fertile. @ Buck, hinnies that I raised as a kid never laid eggs.

 

[Buck Oakes]

Oh sorry, it's been awhile since I read up on them