interspecies romance

I have a male canary in a very large aviary style cage. I wanted him to have some company but not another canary male or female for the obvious reasons. I settled on a female diamond dove figuring she would keep to the bottom and he the top but provide a sort of companionship when I'm not home. Everything I read said they were good aviary birds.

It's day 2 since I brought her home and to my surprise Mr. Canary is incessantly trying to mount her. I'm very concerned this will stress her out, although she doesn't seem to put out by it just yet. I had no idea such different species would try to breed. Should I separate them? Introduce a third bird? thanks for advice