Of course, the name 'harvester' suggests that the ants only eat plant material but that's not necessarily the case. They will eat pretty much anything that contains a bit of nutrition. They do eat seeds in abundance however, mainly from grasses. Several of the grass species actually seed themselves and grow on the ant-hill waste heap so food is just on the doorstep for the ants. The seeds of many other plant species are also favored by harvester ants as is the pollen and nectar from many flowers.

Carnivory

A wide range of carnivorous behaviors is reported for harvester ants. These include the feeding of unhatched eggs by the queen to her first brood of offspring and, in the Florida harvester, the feeding of special sterile eggs, laid by the workers, to juveniles. These are called trophic eggs and this behaviour is unique to this species. There are no reports of cannibalism in any harvester ant species so the ants in your ant farm should be quite safe from each other? Termites, many castes of which are soft-bodied and defenceless, make up about two thirds of their meat intake. Other larger insects, such as grasshoppers and crickets form the remainder, often the ants will remove the soft tissue from the inside of the insect's exoskeleton if they cannot move the entire insect to the nest.

Foraging behavior

The most common foraging strategy is individual foraging. In individual foraging, singleton workers will leave the ant nest to forage for food alone. This is thought to be the most primitive of the hunting strategies but also one that is likely to result in the highest rate of losses. An individual ant is much more likely to be predated upon by another insect or bird than is an organised group. This brings us to group foraging behaviour which is one of the most fascinating phenomena in the insect world. Many species, including the Florida, western and red harvester exhibit this behaviour and this is one of the reasons for their success. Occasionally, you may find an ant column that's over a hundred feet long and a couple of inches wide. Imagine what they will do to any small animal that gets in the way. When a group attack takes place the insect (it's usually an insect) is cut up and taken back to the nest. Often different ants will assume different roles when dealing with prey, from attacking, to dismembering and even digging underneath large prey to make it easier to move. Although the armies of harvester ants on the move are a fearsome sight to many animals, it should be remembered that not all foraging trips are successful. The scouts fail to come back with any food about 40% of the time. So the ants in your ant farm ought to be eternally grateful that you are providing them with food without their having to move from their doorstep.