I'll Be Out Of My Mind, And You'll Be Out Of Ideas Pretty Soon

How do they even know if swans or lobsters or penguins mate for life?

Is there someone in the world whose job is to keep track of these species and which ones are together and which ones are not? Like animal paparazzi, keeping tabs on their relationships at all times?

I would like to see scientific research supporting the evidence, because so far, google isn't doing it for me.