Stingless bees (‘meliponines’) make up around 500 species worldwide. They are closely related to common honey bees, carpenter bees, orchid bees, and bumblebees. Despite their unique and fascinating features, they often get overlooked. Highly regarded and sacred in many cultures, they also play an important role in ecology. Unlike their more common counterparts, stingless bees do not have any visible stingers or venom sacs. Nevertheless, they are prolific pollinators and produce large amounts of honey with a distinctive flavor that is unlike any other type of honey.
Stingless bees make up around 500 species worldwide and are capable of living anywhere from the tropics to desert regions. They are a keyfactor in our ecosystems and must be protected and conserved.
Stingless bees are native in tropical and subtropical regions across the world. They live in Australia, Africa, Southeast Asia and America. Most native eusocial bees of Central and South America are stingless. Some people farm stingless bees for their honey. In in Africa and Madagascar people also farm stingless bees. These bees and their unique honey are considered sacred in most African, Mexican and South American cultures.
Introduction to the Stingless Bee Species
As the name already suggests, stingless bees have no stinger. These insects have a wide range of behaviors and biological features. They’re relatively small in size and live in colonies that are much smaller than those of other bee species. Even though they do not sting, they will defend their nest by biting if disturbed.
Some stingless bee species in the genus Oxytrigona also secrete a liquid from their mandibular secretions as a form of defence that includes formic acid, which causes painful blisters.
Because they live in tropical and subtropical climates, stingless bees are active all year round. However, in cooler weather some species go into diapause. Stingless bees feed exclusively on nectar, pollen, and honeydew from flowering plants. They play an important role in pollination and can also produce honey for human consumption.
Habitat of Stingless Bees
The distinctive hives of Meliponines are quite unlike those of other bee species. As beneficial pollinators, stingless bees require a sheltered environment to build their nests. This allows them to remain safe from predators and allows them easy access to the necessary resources they need to grow and reproduce.
Stingless bees often construct their hives in the hollows of trees, underground cavities, rock crevices or termite nests.
However, these little creatures are also known to use pretty much anything they can find to make their nest. They have used rubbish bins, water meters, and even plastic drums to build their nests. Beekeepers often transfer the hive into something where they can control the hive better.
The actual hives consist of small egg-shaped pots of beeswax mixed with different types of plant resin (cerumen). On many occasions these pots are constructed around a central set of horizontal brood combs that contains the larvae.
The pots are filled with honey and capped with a waxy plug to protect it from environmental elements. The larvae are not fed by workers like the larvae of their honeybee cousins and many social wasps. Once the workers emerge, they usually stay inside the hive performing different jobs. The remaining sections of the nest cavity, including the entrance tubes, are usually lined with a combination of wax, plant resins (“propolis”), and other materials. Given the right conditions, these bees can continue to inhabit their hives for many years at a time!
The Unique Anatomy of Stingless Bees
Stingless bees have some unique physical features which can help to distinguish them from other bee species. They are slightly smaller than honey and bumblebees, measuring only 4-5mm in length. Unlike their other bee relatives, stingless bees do not possess stingers. Instead, they have a sharp, elongated mandible on their heads they use as an effective defense mechanism against predators.
Meliponines have two sets of wings, a longer forward set and a shorter rear set with the antennae bent inwards at an angle of 90 degrees.
Stingless Bees Social Behaviors and Characteristics
The social behavior and characteristcs of stingless bees is unique. They live in colonies with up to 300 individuals, but the number can be much higher in some cases. These bees are capable of communicating quickly and effectively with each other via a complex language of pheromones and vibrational signals. Additionally, these bees display cooperation by practicing animal-assisted pollination activities such as transferring pollen from one flower to another.
In 2012, researchers discovered that some stingless bee species have a special caste of “defenders” to protect their nest entry from invaders. At least 10 species have these “soldiers”, which are larger and possibly a different color than the regular workers. Examples include Tetragonisca angustula, T. fiebrigi, and Frieseomelitta longipes.
Reproduction & Pollination Habits of Stingless Bees
Stingless bees practice animal-assisted pollination activities, most often relying on a hive-based process. The younger bees collect food such as pollen on their hind legs. They store the pollen in the hive, where it is mixed with saliva and propagated. Reproduction among stingless bee colonies occurs during winter when brood production significantly increases, enabling them to produce more than three generations per year.
The social structure of meliponines is distinct from that of other bees due to its variable caste system. This system is largely determined by the amount of pollen consumed during the larvae stage. A higher consumption typically leads to the formation of queens. Unlike honey bees, meliponines are more flexible and can form queens based on the amount of food consumed.
In addition to their variable caste system, meliponines also differ from honey bees in terms of their colony structure. Instead of having a single queen as in other species of bee, multiple queens often exist in meliponine colonies, resulting in more complex social structures. Multiple queens also lead to higher levels of cooperation among the bees within a colony, as workers help feed and tend to the offspring of other queens.
When a hive is preparing for a new queen, the process may involve both environmental and genetic components. Generally, up to 25% of the female brood in a given hive may become queens, though this number ranges from 5-14%. Queen cells can be identified by their larger size, caused by the extra pollen packed within. In some cases, queen cells and worker cells may look the same, making it difficult to tell them apart.
Once the queens have emerged, they usually go off in search of mates before most die shortly thereafter. The surviving queens then take to colony founding, or the process of creating a new hive from existing resources. By this time, the hive is ready to start another cycle of life.
Adaptations for Sustainable Survival in Adverse Environments
The adaptability of stingless bees is reflected in their genetic composition as well as in their ability to survive even under changing climatic conditions. They possess a range of properties that enable them to survive through environmental stresses like temperature fluctuations, competition from other social bee species, parasites, and food shortages. Some of these capabilities include the ability to adjust their brood production according to local conditions; the forming of colonies with related female queens; the concentration of gene pools in closed populations; special defense mechanisms against predators; and efficient communication features to inform one another about food sources.