What is Pollination?
Pollination is an ecosystem process that has evolved over millions of years to benefit both flowering plants and pollinators. Pollinators visit flowers for many reasons, including feeding, pollen collection, and warmth. When pollinators visit flowers, pollen rubs or drops onto their bodies. The pollen is then transferred to another flower or a different part of the same flower as the pollinator moves from one location to the next. This process is a vital stage in the life cycle of all flowering plants and is necessary to start seed and fruit production in flowers. Not only do pollinators provide essential services in nature, they are also necessary for healthy, productive agricultural ecosystems as they ensure the production of full-bodied fruit and fertile seed sets in many crops.
What types of pollinators exist?
There are over 200,000 types of pollinators on Earth – the most known species include:
What are the Values of Pollinators?
Animals pollinate approximately 75 percent of the crop plants grown worldwide for food, fiber, beverages, condiments, spices, and medicines. It has been calculated that one out of every three to four mouthfuls of food we eat and beverages we drink is delivered to us by pollinators. As such, agricultural products that are produced with the help of pollinators make a significant contribution to the economy. For example, it has been estimated that insect-pollinated crops directly contributed $20 billion to the United States economy in the year 2000. If this calculation were to include indirect products, such as milk and beef from cattle fed on alfalfa, the value of pollinators to agricultural production would be raised to $40 billion in the United States alone.
Not only do pollinators provide us with a significant amount of the food we eat and contribute to the economy, they also perform key roles in natural ecosystem. By helping to keep plant communities healthy and able to reproduce naturally, pollinators assist plants in providing food and cover for wildlife, preventing erosion, and keeping waterways clean. Pollinated plants produce fruit and seeds which are a major part of the diet of approximately 25 percent of bird species, as well as many mammals. Flowering plants also provide egg laying and nesting sites for many insects, including butterflies. Pollinators support biodiversity, and there is a positive correlation between plant diversity and pollinator diversity.
Decline of Native and Non-Native Pollinators
Human activities have destroyed and fragmented many native pollinator habitats. Many remaining habitat areas are isolated and degraded by invasive plant species, making them less suitable for pollinators and other wildlife. These changes in habitat can lead to a reduction of pollinator food sources and sites for mating, nesting, roosting, and migration. Excessive use and improper application of many pesticides impact pollinators and their habitats. Some insecticides directly kill pollinators, particularly pollinating insects, and herbicides reduce forage plant diversity by killing wildflowers. Non-native pollinators, such as honeybees, can out-compete native pollinators for local nectar resources, placing them at greater risk of decline. The destruction and fragmentation of pollinator habitats have led to significant declines in many populations. At least 185 species of pollinators are considered threatened or extinct by the World Conservation Union (IUCN), and at least 2 bat and 13 bird species listed as endangered in the United States are pollinators.
Because of the ecosystem services they provide and their unique adaptations to local climate, soils, and vegetation, pollinators are immensely valuable to the environment and the economy. Despite their value, pollinators are declining and often under-appreciated in terms of their services to healthy ecosystems. Human activities have destroyed and fragmented pollinator habitats. However, landowners can work to increase pollinator habitats on privately-owned lands by planting appropriate vegetation, providing water, limiting pesticide use, and providing the habitat needs for specific groups of pollinators (bees, butterflies, moths, flies, beetles, bats, or hummingbirds).
Our Earth Needs Pollinators For Future Sustainability!