Wasps, recognized by their slender bodies and narrow waists, are insects belonging to the order Hymenoptera, which also includes bees and ants. While bees are celebrated for their role in plant reproduction, wasps also contribute to pollination. Their involvement, though less apparent than bees, is part of their ecological function.
How Wasps Pollinate
Wasps possess fewer hairs than bees, making them less efficient at pollen collection. Pollen grains still adhere to their bodies and legs as they move between flowers. Wasps visit flowers primarily for nectar, for energy. Unlike many bees, most wasp species do not collect pollen for their larvae, as their young are carnivorous.
Foraging for sugary nectar results in incidental pollen transfer. Wasps are attracted to flowers with easily accessible nectar, often with shallow floral structures. Some wasp species, like pollen wasps (subfamily Masarinae), are an exception; they feed solely on nectar and pollen, provisioning nests with plant-based resources for their young, similar to bees. These “vegetarian” wasps gather pollen internally, not externally on body hairs.
Pollination Partnerships
While often generalist pollinators, some wasp species are specialized, playing a role in specific plant reproduction. A key example is between fig trees (Ficus species) and fig wasps (family Agaonidae). Each of the nearly 1,000 fig tree species relies on a particular fig wasp for pollination, demonstrating a co-evolved, obligate mutualism.
The fig wasp’s life cycle is linked to the fig’s development. A female fig wasp, laden with pollen, enters a developing fig through a small opening. As she navigates the fig’s interior, she pollinates tiny internal flowers while laying her eggs. The fig provides a sheltered nursery for the wasp larvae, and in return, the wasp ensures the fig’s seeds are fertilized, necessary for the fig tree’s reproduction.
Orchids also partner with wasps. Some orchid species, particularly in the genus Ophrys, mimic female wasp appearance and scent. These orchids attract male wasps seeking to mate; pollen attaches during their attempts. When the male wasp visits another orchid of the same species, it transfers the pollen, facilitating the orchid’s reproduction. This interaction shows how wasps contribute to plant diversity.
Wasp’s Broader Ecological Contributions
Beyond pollination, wasps contribute to ecosystems through other roles. Many wasp species are natural pest controllers. They prey on insects and invertebrates, including agricultural pests (e.g., caterpillars, aphids). This predatory behavior regulates insect populations, benefiting agriculture and maintaining natural plant communities.
Social wasps (e.g., yellowjackets, hornets) also act as scavengers. They consume carrion and other organic matter, contributing to nutrient cycling. This scavenging activity breaks down dead organisms and returns nutrients to the soil. The diverse roles of wasps—from specialized pollinators to pest controllers and scavengers—show their value in maintaining healthy ecosystems.