Are they fighting?

[Duckingham palace]

Hi I’m looking for advice I’m new to being a duck mama and I have a rescue mallard and 4 white campbells I’ve noticed today 2 of my whites look like they are fighting. What do you all think

 

[sourland]

They may be or it may be mating behavior.

 

[Duckingham palace]

They may be or it may be mating behavior.

I’ve been trying to upload a video but I can’t so added screenshots. Still not sure what sex they are.