Yes, female swans will pair with females and males with males if the opposite gender is not available. The females will lay eggs, but obviously, they will be infertile. They will sit on the eggs until they figure out nothing is going to happen. Usually, 1-2 weeks at the most. Hopefully, they are not building in the same area with the coyote, because it will return.

How do you know that the new swan is a female? Unless, they have been sexed, using DNA sequencing as the most reliable method, you cannot tell by looking. Was this a swan you had as part of your flock and had it sexed? Just curious. And, yes, if there is not another male, these two will stay together. The Regal Swan