What layer of the amazon rainforest does a jaguar live in?

Previous answer: They hunt mostly at ground level but sleep in the trees.

That's interesting. I guess that since they "hunt" mostly grasses, that is at ground level. Capybaras do not prefer to live in forests. Their perferred habitat is swampy grasslands or lake edges. They require open areas for grazing, water for swimming, drinking and evading predators and also like a little cover such as a forest edge for shade and predator avoidance.