One thing pointed out by David and Matt is that my camouflaged Gorgosaurus are so well camouflaged they pseudo blend into the background.
I have tried a few things to fix this. Sadly to no avail.
The first was trying different depths of view. Sadly this hasn't worked out well due to the controls on Carrara's tool for this and the scale I built this scene at (which is more my fault than Carrara. I need to remember to build things on a real world scale so they match normally).
Here the camera is focused on the Troodon.
Yet this still doesn't really help truly pop the Gorgosaur out at all.
My other solution has been a light blue mist. This has helped, but only with the tree line and not the shrubs at mid level in the picture.
So probably tinker more in this department.
Next I wish to populate this pic with some more smaller feathered theropods. Probably another Troodon or two, and some others...