Let’s Talk pollination
Most plants reproduce through their flowers by a process called “pollination.” Pollination occurs when the pollen from the male anther (the part of the flower that contains pollen) is transferred to the female stigma (the part of the flower that receives pollen). Flowers rely on vectors to carry pollen from one flower to another. These vectors can include wind, water, insects, birds, butterflies, moths, and any other animals that may visit the flower. These animals and insects that transfer pollen from plant to plant are called “pollinators.”
In Ireland, some of our main pollinators include various types of bees, hoverflies, butterflies, moths, birds, beetles, and more.
Our friends, the bees!
Bees are by far the most important pollinators in Ireland; most pollination on the island is carried out by bees. This is because bees feed their young exclusively on pollen, so they are entirely focused on collecting it from flowers to bring back to their nests. In Ireland, we have 98 different types of bee: the honeybee, 20 different bumblebees and 77 different solitary bees (“solitary” meaning they work alone and do not form colonies). The variety in bees and other pollinators is important, as it helps to maximise pollination.
As their name suggests, honeybees are the ones who gift us with the delicious fruits of their labour—honey! These bees live in complex colonies, filled with bees of all different kinds of roles, including scout bees, pollen gatherers, guard bees, nurse bees, and more. When worker bees, when they return back to the hive, they perform a “waggle dance” for all their friends. This lets others in the colony know where all the good food sources (pollen and nectar) are located!
Solitary operate outside of a colony. Working alone, female solitary bees build their nests in hollow stalks, reeds, or twigs as well as tubular tunnels in soil, sand, clay, or wood. They build individual cells for each egg, repeating the process until the tube or hole is full, sealing it off with materials such as mud and leaves. These bees do not care for their larvae. Instead, they collect food and leave these provisions with their eggs, so when each egg hatches, the larvae feed on the pollen and enter hibernation in the cocoon until spring, when the adult bees emerge from their nest. Insect hotels can provide an excellent nesting space for the solitary bee. Learn how you and the little ones can make one for your garden here.
Bumblebees are one of Ireland’s key pollinators. In a colony, there is typically one queen bee. The queen is a larger, fertile female bee who will seek out a suitable nest site in early springtime. Frequent nesting sites include holes in the garden, grass, bird boxes and under garden sheds. Once she has identified her nesting ground, she will start to lay her eggs. The queen keeps her eggs warm by sitting on her wax nest and shivering her muscles to keep warm. She does this for several days until grub-like larvae emerge. These larvae feed on pollen and nectar which the queen goes back-and-forth to collect from nearby flowers. Once they have eaten enough, they develop into adult bees. These first brood of adult bees are known as worker bees and forage for food (pollen and nectar), build and protect the hive, and keep the air within the hive clean by beating their wings. The queen bee continues to lay eggs but stops leaving the nest; instead, she continues to order her worker bees around. As the late summer approaches and the last brood of eggs have produced into adult bees, we start to see more male and females in the hive. Males (known as drones) usually leave the nest to mate and tend not to return. Once they mate with a queen, they tend to die.
A queen bee is created thanks to the efforts of existing worker bees in a hive. A young larva is fed special food called “royal jelly,” which is necessary for the larva to develop into a fertile queen bee.
There are 20 different species of bumblebees, which can be identified by their varying colours and stripes. Some are more rare than others and are threatened with extinction, so a FIT Count is important for tracking changes in abundance.
There are many different species of hoverflies in Ireland. These important pollinators mimic bees and wasps to protect themselves from predators in the wild. Because of this, they’re often confused with bees. As their name suggests, they hover around flowers when feeding on delicious nectar and pollen. Hoverfly larvae can serve as a natural pest control, as they feed on certain insects such as aphids.
Butterflies and moths
Once our legged friends transform into winged friends through metamorphosis, their diets change from feeding on the leaves of plants to feeding on mostly nectar—but also pollen. While they don’t carry quite as much pollen as bees, butterflies and moths are capable of carrying it over greater distances, giving them an important role in pollinating Ireland. In fact, the Painted Lady travels from Morocco to Ireland, covering 2,000km in just one month!
When we think of pollination, bees often come to mind. And while bees are the most important pollinators here in Ireland, birds also have a role to play. As birds fly from flower to flower, feeding on delicious nectar, they unknowingly brush up against pollen and carry it with them to the next plant. But even the non-nectar-eating birds have a role to play! Some birds feed on the insects that live off flowers, so these birds also collect pollen in their wings when feeding on insects and can spread it great distances.
Beetles were one of the first insects to visit flowers, and while their role isn’t quite as important as the bee’s role in pollination today, they certainly help to pollinate. As they move from flower to flower, feeding on pollen and other parts of the flower, they leave their waste as they go. This has earned them the not-so-flattering title of “mess and soil” pollinators. Because these insects cannot fly or hover over flowers to feed, they tend to visit bowl-shaped flowers that are open during the day. These are easier for beetles to access.