Though the hippo looks dried out there is still plenty of food inside and the crocodiles have been stretching into the cavity to feed. Many insects also feed at night, including crickets. Some crickets are predatory and eat the maggots around the carcass whereas others stay on the carcass itself. The smell of the decomposing carcass is caused by bacteria which produce gases. These gases travel huge distances and attract insects which sense them using their antennae. There could be 100 different insect species on the carcass.