That's exactly what I was worried about. I figured with how violent drakes can be, disaster looms!Calls are seasonal layers only, but how well they lay depends on lines and whether they're super tiny SQ or larger PQ... my PQ and BQ ones lay fairly well... my Snowy line lays much less...
I have had them with Rouen mixes and Swedish just fine... but, if you have a standard sized drake, I do not recommend Calls with them, they can seriously injure if not kill the smaller ducks...
I do have a large fenced garden - Maybe I'll set something up for a pair in there sometime. What variety is the bird in your photo?