The Indian subcontinent during the Eocene was an island beginning its collision with Asia, which would eventually lead to the uplifting of the Himalayas. India had a hot climate with tropical rainforests and coastal mangroves. Ambulocetus was found in an area which was a shallow sea off the shores of a coastal swamp or forest, and it may have predominantly inhabited brackish areas such as at a river mouth. It lived alongside requiem sharks, fish, catfish, turtles, crocodiles, the amphibious mammal Anthracobune, and the cetaceans Gandakasia, Attockicetus, Nalacetus, and Pakicetus.