Why Are These Chicks Black If The Father Is A White Plymouth Rock?

[Pretty Birds]

My broody Austra White pullet hatched six chicks! The father is a White Plymouth Rock, and the mothers are/could be Cuckoo Marans, Speckled Sussexs, Easter Eggers, a Delaware, a Buff Orpington, a Barred Plymouth Rock, or Golden Comets. I know one chick is half Maran, because the dark brown egg hatched. I also know one is an Easter Egger because the green/blue egg hatched, and one of the chicks has a beard and pea comb.
I was expecting a bunch of different colored chicks, but they are all black and yellow! They have different amounts of yellow; some are half yellow, and some just have yellow on the top of their heads, and some are in between. I know it must be because of the father, but how can that be if he is white?

 

[The Moonshiner]

Your rooster is recessive white.
He is a basic black bird and has two copies of recessive white which makes him white.
His offspring are only getting one copy so its not being expressed hence them being black.
Your barred/cuckoo hens are producing black sex links when crossed with him.
Expect the ones with yellow spots on their heads to be males.

 

[Cyprus]

White is recessive to black. The chicks all got one copy of dominant black, therefore are black.

 

[The Moonshiner]

No worries. We all make mistakes or miss things, sometimes.

Lol ya. Not too big of a deal it just slipped my mind which reminded me I'm getting old.
But also good to show when i do screw up I'm not afraid to admit it.

 

[The Moonshiner]

Any with head spots are males.
Any without head spots could be either sex since with your nonbarred hens your not producing sex links.

 

[NatJ]

After staring for a while at both videos, I think the single-barred sexlink rooster in one video has a larger head spot than any barred rock in the other video (single-barred hens or double-barred roosters.) So I'm going to assume there's some kind of modifier genes at work, in addition to one vs. two copies of barring being present, possibly also with the addition of gender-specific hormones as suggested by nicalandia.

Nothing like a bit of confusion about something that started out seeming simple...

 

[cmfarm]

The hens without any barring would not be sex linked, but will be barred if they have the dot on their head.

 

[nicalandia]

The post from nicalandia would assume that the mother of those possibly female chicks was barred or cuckoo.

Not necessarily,

E/E, B/B rooster mated to none barred female will yield Heterozygous Barred males(B/b+) and Hemizygous barred females(B/-), the males will still be identifiable from the females, females have a faint barely noticeable headspot, males even with heterozygous Barring(B/b+) will have a larger undefined headspot the will extend to the back of the head area just like your typical sex link chicks..

Black Sex link chick(E/eWh B/b+ chick)

 

[NatJ]

E/E, B/B rooster mated to none barred female will yield Heterozygous Barred males(B/b+) and Hemizygous barred females(B/-), the males will still be identifiable from the females, females have a faint barely noticeable headspot, males even with heterozygous Barring(B/b+) will have a larger undefined headspot the will extend to the back of the head area just like your typical sex link chicks..

Black Sex link chick(E/eWh B/b+ chick)

I think you've got that backwards. Black sexlinks come from a non-barred rooster bred to barred females (example, Rhode Island Red rooster with Barred Rock hen): so only the sons get barring (head spot), and the daughters are all black (no head spot). I don't see how you'd tell a male with one copy of barring from a female with one copy of barring.

For the OP's chicks:
If the White Rock father is barred (hidden by the white), then all chicks would carry one copy of barring. The chicks who have a barred mother (Marans, Delaware, Barred Rock) will have a larger yellow spot on the head IF they are male (because a male can have two copies of the barring gene, B.) Any female chicks, and any male chicks whose mother was not barred, should have a smaller or not-present head spot (because they'd only have one copy of B.) The chick from the Easter Egger, for example, will not be sexable by head-spot.

 

[The Moonshiner]

You've lost me because in the past I hatched quite a few single barred male and barred female leghorns and they look identical at hatch all the way to adulthood as far as head spots and barring.
Maybe it has to do with my breed being fast feathering Idk.