Introducing ducklings to ducks

Hey all—
New duck owner and 1st-time poster. We just acquired 3 ducklings to add to the flock. They’re about a month old. When we introduced them to our yearlings one of the drakes nipped at the ducklings. Any opinions on when/how to integrate the ducklings to the rest of the flock so that the drama stays at a minimum? Thanks!

It might be best to keep them separated with a wire fence so they can see each other/get used to each other without the ability to attack.  I do this for a few weeks when introducing new chicks to my flock of hens.  If they are a similar size/age to begin with, I only keep them separated this way for a few days.  When it's time to integrate I let them free range together for another few days--this way everyone has plenty of space to escape from fights.  

I don't think it's likely your drakes will be able to kill one month old ducklings;  at that age they should be big and heavy enough to either stand up for themselves or run away quickly.  Good luck.

Welcome to permies, Timothy!

Yes, letting them see each other is step one.
How many adult ducks are you talking about, and how many drakes?
Have you considered moving just one of your calmer female ducks in with ducklings for a few days to see if she'll "mother" them a little. How well that works depends on the temperament of the older duck, but I've had that work before. Look for a duck that tends to spend more time in a nest box when she lays as that could be an indicator.
I'd also consider introducing them for only short periods, well supervised, the first few times if the surrogate mom idea doesn't work.
In a perfect world, I'd have "neutral ground" for the first introduction, and a treat that everyone likes so they get used to the ducklings while chowing down on something like Kale or Duckweed.