That was back when dinosaur sized birds were running around. Of all the animals I'd hate to see "supersized", I'd have to say it's a toss up between Insects and Birds. Insects because they just bother me and Birds because they have such great eyesight and are so quick.
I think I would be to frightened to sleep. We still have a metre long earth worm here in Australia that has teeth like Bugs Bunny. Imagine camping out and having one of those visit you through the night.
Two things scarier: the food they ate, relative size bearing as a factor, a sardine would have been really big, to big to fit in a tin, and the size of the predators that fed on them would have been monstrous in comparison perhaps it is a good thing they went the way of the dodo