What whale only has one mate?

Answer 1

None. Whales don't practice monogamy. In the past, it was thought that they did but recent genetic testing has shown both male and female whales may have a multitude of different mates. This is true for all species of whale.

There have been claims by some activist groups that some whale species mate for life, but there is no evidence to support this. Whereas there is plenty of real evidence to say otherwise. They generally argue this to "humanize" the species and to lobby support for their cause. While their hearts are in the right place, they are factually wrong.

True monogamy is actually rare in the animal kingdom.

Answer 2

Swans and doves