Call duck drake attacking bantam rooster

[easterlyfarms]

currently i have my calls (drake and hen) separated from the Chickens (rooster and hen). As soon as mating season arrived the drake has shown aggression toward my rooster. they were living in harmony from the beginning of their lives. the drake clamps on his feathers and does a alligator roll. when the rooster gets him off the drake ends up with a peck bald head and clawed. i separated them before anything bad happens. I am wondering if it will just pass over with mating season, or i should let them fight for one to establish dominance. will this be permanent? Also he seem to show aggression toward the standard hen but is very hesitant for she has clobbered him a few times. What should i do? any insight would be wonderful