I have a drake that is the sweetest thing to his gal. He is very protective of her and I have never seen him be rough with her in any way. 
		
		
	
	
  here he is standing guard over her and her eggs. 
I don't know how it was before I got them. .. But as for what I've seen so far there haven't been any signs of over breeding or violent breeding. I have spent a LOT of time watching them and I I have rarely even seen them breed. This may not be the norm. . but it's evidence to me that having pairs is not always a disaster. 
I got three ducklings from that hatch, I brooded them myself because my enclosure was not duckling proof at that time. . . of course two turned out to be drakes
 
 For the second hatch I didn't learn my lesson the first time and did not have the enclosure fixed yet for 'lings. Mamma Jane was not having me taking her babies again! So she got brought in to the brooder with them while we worked on their enclosure. I did end up having to separate My drake from her and the 'lings because he was just too freaked out by the whole experience. I honestly think he would have been ok with them had I not had to remove them and put them back and make such a ruckus. I will give him the chance next time but I do understand it may not work out. 
Poor duck was miserable the entire time he was separated from his love. 

And she missed him as well. 
 
The two drakes I kept from their first offspring seem like they will be a lot like their daddy. Over the summer when they came into their hormones they were obnoxious for a bit but it was short lived in the big scheme of things. Despite the warnings about drakes becoming human aggressive if handled a lot and kept as pets. . mine are not. There was about a week or so I had to make them understand that I was boss. . but they have not challenged me or anyone else since then. They aren't lap ducks by no means but they are more interactive with me than the girls are, curious about everything I am doing and are the first ones to run to me for treats. 
As far as being hard on the girls, one drake did spent most of the summer in lock down for being a jerk. 
but. . it was partially, I feel, due to the addition of three new gals on top of the budding hormones. 
The brother to him accepted the new girls just fine within a few days. 
I actually had a harder time with my female accepting the newbies. 
Now that all that is over with they all get along just fine. . meaning two drakes with the four female ducks. 
My original pair I have kept separate from the others.. . not because of the drakes having a problem getting along or being aggressive with girls but because the girls beat up my sweet drake! Further evidence that drake s are not *always* the problem children. 
