Mason bees are remarkable insects that play a significant role in ecosystems as early spring pollinators. These solitary bees primarily rely on floral resources for their sustenance, which directly supports their active life cycle and the development of their offspring. Understanding their specific dietary preferences and foraging behaviors provides insight into their effectiveness as pollinators.
The Adult Mason Bee’s Diet
Adult mason bees primarily consume nectar and pollen directly from flowers for their own metabolic needs. Nectar provides carbohydrates, serving as an immediate energy source for flight and daily activities. Pollen, rich in protein and other nutrients, supplies the building blocks necessary for muscle maintenance and overall bee health. Unlike social bees, mason bees do not produce or store honey; they consume resources for immediate energy and nutrition.
Nourishing the Next Generation
Female mason bees gather a specialized mixture of pollen and nectar to provision their young. This prepared food, often called “bee bread,” is deposited within individual nest cells. A single egg is laid on this nutrient-rich mass, providing the sole food source for the developing larva. The larva consumes the bee bread over several weeks, undergoing growth and molting within its sealed chamber. This provision supports the larva’s development into a pupa and eventually an adult bee, which emerges the following spring.
How Mason Bees Collect Food
Mason bees possess a unique method for collecting pollen, differing from honey bees. They do not have pollen baskets on their hind legs. Instead, pollen adheres to specialized, dense hairs called a “scopa” located on the underside of their abdomen. As they move from flower to flower, pollen easily dislodges from their scopa, facilitating efficient pollination. This “messy” pollen collection, where pollen is carried dry and loosely, contributes to their effectiveness as pollinators because more pollen is transferred with each floral visit.
Favorite Foraging Plants
Mason bees are particularly attracted to early spring blooming plants, which align with their emergence period. They are generalist pollinators, meaning they forage on a wide variety of plant species rather than specializing in just a few. Many fruit trees, such as apple, cherry, and pear, are preferred sources due to their abundant pollen and nectar, making mason bees valuable for orchard pollination. They also frequent berry plants like raspberries and strawberries.
Beyond fruit trees, mason bees forage on dandelions, Oregon grape, and various types of clover. They also visit accessible flowers with single rows of petals or composite flowers, including poppies (valued for their pollen), lavender (offering both nectar and pollen), black-eyed Susan, forget-me-nots, and mints. Mason bees typically forage within 100 to 300 feet from their nesting sites.