Is this Hornbill small or is that caterpillar huge?

There’s an African Grey Hornbill flying past our 4×4 in the Masai Mara. It’s come from behind and is flying away by the time I see it.

In its bill is a caterpillar. As I look at the back of my camera, I wonder, Is this Hornbill small or is that caterpillar huge?