Harvesting from nature can be done by farmers but very often it is an activity by villagers or by special collectors. For example in the case of the mopane caterpillar in southern Africa, collectors (very often women) travel long distances to collect in the wild (in Zimbabwe for example they obtain contracts from large farms in order to harvest). The mopane caterpillar is one of the best known and most economically important forestry resource products of the mopane woodlands in southern Zimbabwe, Botswana and the northern South-Africa. It has been estimated that annually 9.5 billion mopane larvae are harvested in South Africa’s 20,000 km² of mopane forests worth US$ 85 million, of which approximately 40% goes to producers who are primarily poor rural women. Increased supplies of mopane caterpillars in both rural and urban areas therefore have the potential to address food security problems both by increasing incomes for poor mopane harvesters or producers (providing financial capital for food purchases) and by increasing the availability of a high-protein and popular food.

In Laos it was also found that most villagers engage in collecting for home consumption and/or for the market. As such it provides both income and a high quality food source.

There are numerous studies about the nutritional value of insects. Sometimes they are difficult to compare because of lack of standardized methodologies. Also the many edible species all differ in nutritional value. Even the chemical composition of related species may vary as it often depends on the plant they feed on, so it is location specific. However, some generalizations can be made. The protein content is comparable to that of conventional meat. The essential amino acids are often present, but the protein quality of each insect should be considered in relation to the dietary staple. The fibre content (chitin from the exoskeleton) is higher than in conventional meat but comparable to that of cereal grains. All food insects are a significant source of short chain polyunsaturated fatty acids, a good source of iron, calcium and B vitamins. In general as a food group, insects are nutritious, rich in protein and fat, providing ample quantities of minerals and vitamins. The amino-acid composition is in most cases better than that of grains and legumes.

Insects can be used as complementary feed source for livestock. Most promising for industrial production are the larvae of soldier fly, housefly, mealworm, silkworm and grasshoppers. Feeding animals with protein sources such as meat meal, fish meal and soybean meal often represents up to 60-70% of production costs. Another increasingly serious environmental problem of livestock is manure disposal. The Black Soldier Fly is able to reduce the manure pollution potential by 50-60% through nutrient concentration. It also reduces noxious odours, harmful bacteria and housefly populations. As a component of a complete diet they have been found to support good growth of chickens, swine, rainbow trout, channel catfish, and blue tilapia. Housefly larvae can provide an excellent source of animal proteins for local poultry farms and their production alleviates the environmental problem of manure accumulation. Also mealworms can be grown on low nutritive waste products and fed to broiler chickens. Growing edible insects on organic waste for livestock feed would allow using grains targeted as livestock feed for human consumption.

The culture of eating insects is based on its collection from the wild. It is possible to treat them as mini-livestock. Some arthropods are already reared on an industrial scale such as edible scorpions in China. Others, such as crickets and water beetles, are reared on semi-industrial scales. In temperate zones, insect rearing companies produce insects as feed for reptiles and primates. In the Netherlands three such insect growers have set up special production lines to produce for human consumption. In other parts of the world attempts are being made to rear insects artificially such as palm weevil, mopane worm, and wasps. Mass rearing methods for maggots and soldier flies as livestock feed are available. These are grown on side streams reducing organic waste disposal problems.

It is known that locusts are not always considered a plague but sometimes as a welcome food source. For that reason in some Arabic countries the use of pesticides for locusts is heavily contested. The harvesting of edible insects can sometimes be used as a control method. In various parts of the world mechanical harvesting of grasshoppers is carried out while using them either as human food or animal feed. In Southeast Asia weaver ant larvae and pupae are a very popular dish, but at the same time the ants can be used in orchards as a biological control agent. Methodologies are being developed to combine harvesting of the ant as food, and promoting its biocontrol potential.

As with other foods, edible insects can also be associated with food safety hazards (FAO 2021).