Birds, along with bees, butterflies and other insects, play an important role in helping flowers to reproduce. The birds search for food, shelter, mates and nesting material among the flowers. In turn, they carry the pollen from one flower to the next, helping to pollinate the plants. Gardens or landscapes that provide attractive flowers while also offering valuable resources for birds help to continue the cycle.
Flowers act as the reproductive structure of the plant. Pollination consists of the transfer of pollen from the male anther to the female stigma. Pollen consists of a highly nutritious, sticky substance with lots of protein, making it an ideal food for some birds. Sometimes pollination occurs in the same plant, while other times it occurs between two different plants.
Flowers produce both nectar and pollen. While some plants rely on the wind to help take pollen to the female plants, others depend on birds to spread their pollen. The bird becomes known as the pollinator since it helps spread the pollen. To get birds to visit their flowers, the plants must offer a reward, such as nectar and protein-rich pollen. While the bird eats the nectar, pollen sticks to the bird's body, legs, beak and head. When the bird moves to the next flower, some of the pollen on the bird falls off on the stigma of that flower, resulting in the successful pollination of the plants.
Hummingbirds use their eyes to find red, orange or yellow flowers while relying on their long beaks to thrust deep into the flowers for nectar. They leave the flower with faces full of pollen, which they then take to the next flower. Some birds visit flowers to eat small insects attracted to the plant's nectar. In the process of eating the insect, the bird takes some of the pollen to other plants. Sometimes the flowers will produce two kinds of pollen--normal and sterile--with the sterile pollen used to attract birds and insects to the flower for the tasty treat.
According to the U. S. Forest Service, more than 2,000 species around the world feed on a plant's nectar or the insects on or near the flowers. Some of the birds include hummingbirds, tiny birds that weigh as much as one to three pennies, who survive by eating several times their weight in nectar every day. Honeycreepers, with their long beaks perfect for sucking nectar out of deep, tubular flowers, help pollinate flowers in Hawaii. Honeyeaters in Australia and brush-tongued parrots of New Guinea are examples of birds that help pollinate tropical flowers in other parts of the world.
The exchange of pollen between the birds and the plants creates a mutual partnership, called coevolution. Without birds, flowers that rely on birds for pollination would die out in the next generation. Without flowers, the birds would lose an important resource as well, making their species highly susceptible to extinction.