YES YES YES YES YES YES YES YES YES... They are.
A cat killed my bunny
He had free range time in our garden morning before work and evening when I got home for 2.5 years and was the happiest bun I've ever had. I never went far when he was free range and he played with next door's cat very happily. They loved each other (would lay together and even groom each other!). One day I went to shut him away after breakfast and a giant tom cat I'd never seen before was carrying him off. I managed to chase the cat and get him back but it was too late. There were no external injuries so I think he died of shock.
I will never let a bun free range outside again... It was a hard lesson to learn.
The bunny I have now come in the house morning and evening so she still has the chance to explore/play, but never outside unless she's in her run. I know she would be happier playing out but it's too high a price to pay...