The European Hornet (Vespa crabro) is a unique species of wasp native to Europe. Often mistaken for other types of wasps, such as the common wasp (Vespa communis) or the polistes wasp (Polistes gallicus), the European Hornet is actually a valuable ally in the ecosystem. Despite the misconceptions associated with hornets, they play an important ecological role as efficient predators, particularly in controlling the population of the invasive Asian hornet. In this article, we will explore the distinctive characteristics and fascinating life cycle of the European Hornet, highlighting its beneficial contributions to the environment.
About the European Hornet
The European Hornet belongs to the order Hymenoptera and is a member of the Vespidae family. Its scientific name is Vespa crabro. Unlike other species of wasps, the European Hornet is significantly larger, measuring between 18mm and 25mm for workers and up to 35mm for queens. Its body is predominantly black and yellow, with reddish-colored legs. The hornet possesses strong mandibles, which it utilizes to dissect its prey.
A Well-Organized Life
Similar to other social wasp species, the European Hornet exhibits eusocial behavior, meaning it lives in organized colonies with distinct castes of fertile and infertile individuals. Originally found in Europe and northern Asia, the European Hornet has been introduced to North America and North Africa, where it has adapted well to the local environment. These hornets thrive in wooded habitats and display remarkable organizational intelligence within their colonies.
The Life Cycle of the European Hornet
The European Hornet colonies follow a unique life cycle compared to bees. The colony is short-lived and does not survive the arrival of winter, except for the young fertilized queens. In spring, these queens search for suitable locations to build nests made from chewed plant fibers, where they lay their first batch of eggs. Nests can be found in various sites, including stone walls, dead trees, chimneys, attics, and compost piles. The size of the nest can vary but can reach heights of up to one meter.
After the queens lay their first eggs, they establish new colonies, marking the beginning of a new cycle. For the following five to seven weeks, the surviving queens personally care for the first hatched larvae until they molt into workers. Once the workers mature, they assume the responsibility of maintaining and managing the colony, allowing the initial queen to rest. By autumn, the colony reaches its maximum size, and new queens and males are born, setting the stage for the next cycle. The original queen, males, workers, and unfertilized females die during winter, while the newly fertilized queens survive to establish new colonies in the subsequent year.
Impressive Nests
European Hornet nests feature five to twelve rows of overlapping plateaus made up of individual cells. The overall shape of the nest can vary depending on its location and available space for construction. The orientation of the cells always faces downward, and the nest’s color and patterns depend on the plant fibers used by the workers for construction. On average, a European Hornet nest contains 1,500 individual cells and can measure up to one meter in height. In the southern regions of France, where summers are longer, the colonies develop larger nests. The nests of the European Hornet can be distinguished from those of the Asian hornet primarily by their lower placement, as European Hornets prefer lower heights for nesting.
An Insectivorous and Vegetarian Diet
Despite its misconceptions and negative reputation, the European Hornet is not a nuisance but rather an ecologically important wasp. It is both insectivorous and vegetarian. As larvae, the European Hornet feeds on various insects, including wasps, bees, spiders, flies, caterpillars, dragonflies, and grasshoppers. As adults, they adopt a vegetarian diet, feeding on flower nectar, plant sap, fruits, fennel, heather, ivy, blackberry, and blackthorn.
Although European Hornets may consume some bees, they are far from dependent on them as a primary food source. In fact, they are valuable allies for bees, as they prey on gallflies and wax moth larvae, which can cause significant damage to beehives. By controlling these pests, European Hornets indirectly support the well-being of bee populations.
It is important to note that European Hornets may occasionally damage mature fruits by hollowing them out as they reach maturity. However, their overall contribution to ecological balance outweighs any minor impact on fruit crops.
The European Hornet: A Garden Ally
Due to their misunderstood nature and the invasive reputation of Asian hornets, European Hornets are often seen in a negative light. However, they serve as crucial predators of invasive hornets, contributing to the regulation of their populations. If a European Hornet nest is present on your property, it can be left undisturbed, provided a safe zone of at least 4 meters is maintained around the nest to avoid disturbances. It is generally not recommended to remove a European Hornet nest, as they will rebuild in the same location. The colony naturally abandons the nest by early October and does not return the following year.
By understanding the true nature and essential ecological role of the European Hornet, we can appreciate and coexist with these remarkable creatures in our gardens and natural environments.
