Insects such as bees and hornets are not welcome to many human beings occupied spaces. In that category there are wasps. Wasps are mainly known for causing discomfort but they are essential to the environment as part of biodiversity. In some regions people find it difficult to tell the difference between wasps and hornets, their territories are similar. Wasps can occupy a home garage, gardens and bushes resulting in people overlooking their importance in the ecosystem.
Wasps appearances varies across a range of their species but mostly they have shared features. In Zimbabwe, they are usually referred to as ‘mago’ in the local Shona language, the same local name for hornets.
“They prefer human habitats and plant fields. They can mount their nest at the office door way, houses, forests or bushes, where they become part of the ecosystem, occupy a certain territory and defend it. Anyone who passes through or disturbs the nest risks being stung. People end up avoiding such places for their safety,” says Norman Hungwe, an agro-ecologist.
Wasps defend their territories, for such purposes as mating, nesting, roosting, or feeding. In most cases they exhibit territorial behaviour to people who pass through their territory. This involves aggression. The territory acts as a spacing mechanism and a means of providing resources among a segment of the population and denying it to others.
According to Natural History Museum (NHM), wasps range in size depending on their age and species. Wasps are usually small insects with 2 sets of wings and 6 legs like hornets and have a tiny waist. They also have chewing mouthparts to chew prey and other food sources. Female wasps have stingers which are used to lay eggs, they also use the ovipositor to sting when threatened.
In Zimbabwe and all over the world, wasps have a bad record with a number of people having taken a thorough study about these tiny insects. These insects have a paramount role to play in the ecosystem, equally important like other animals, insects and plants. A variety of solitary and social species make up hundreds of wasp types in Zimbabwe. The most commonly seen wasps are the black and yellow social species, common in rural areas and farms.
Tinaye Makanga, a pest control specialist based in Harare says, wasps help in natural pest control and are important in keeping the ecosystem balanced.
“Wasps are very good predators of spiders and other small insects. Of course, humans have reasons to avoid them or destroy them in case they occupy their habitats, but they help us a lot from other dangerous insects. World over, wasps are in thousands which means other insects are preyed on daily. The ecosystem relies on wasps, if only we can appreciate their presence more than the pain of a sting. These are facts many people do not know,” Makanga says.
Wasps are so adept at controlling pest populations that the agriculture industry now regularly deploys them to protect crops.
According to a research by the Natural History Museum in the United Kingdom, every year especially in summer, wasps prey over millions of pest insects such as flies. The capture of insects makes wasps beneficial to their environs, and humans becomes the ultimate beneficiaries.
Researchers say wasps also play a valued role as a pollinator as they fly in the fields and gardens from one plant to another in search of food, thereby spreading pollen grains. Their contribution to pollination may be lower than that of bees, but is still appreciated.
In a report by the Society of Environmental Toxicology and Chemistry titled, ‘The Wasp as a Terrestrial Indicator of Environmental Metal Composition: Evidence from Zimbabwe,’ the scientists examined wasps from different sites in Harare for metal concentrations.
Elevated concentrations where found at 2 presumed-polluted sites (a platinum mine and a known polluted lake) located near a metal-enriched geological feature (the Great Dyke). A site in Harare Urban and a nature reserve served as reference points. Wasps from the visited sites under research had higher concentrations of various metals in comparison with those from other sites. Pollution is the major source of these metals.”
“Due to the fact that wasps form a complex part of the food web and ecology, studies on the transfer of metals to wasps’ predators are needed, especially given that some birds specialize in feeding on hymenopterans,” the report adds.
A research by this reporter shows that, the aculeate wasps are ubiquitous across ecosystems and exhibit diverse co-evolutionary and exploitative associations with other organisms. Wasps perform important ecosystem services as parasites, predators, biological indicators, pollinators, decomposers and seed dispersers; economic benefits can be experienced through their roles in natural pest management and biological.
