April is a month of firsts in Rhode Island. The osprey return, the cherry trees bloom, and mourning cloak butterflies and groundhogs emerge from hibernation.
Today, I encountered my first queen bumblebee of the year. She was buzzing up and down the sidewalk in front of my house, probably looking for a good flower to have her first spring meal.
I know she is a queen because only the queen bumblebees hibernate over winter. After mating with males in the fall, the queens find a cozy underground hole, where they hibernate through the cold season. In spring, these fertile queens begin feeding on flower nectar and gathering pollen for their young.
The queen’s first job is to create worker bees who will help build her colony. She finds a spot to start laying eggs, like an old rodent burrow, a rock pile or under leaves and brush. In the den, she creates waxy pots that she fills with pollen and nectar, and then lays her eggs on top. When the young bees are born, they are literally sitting in their food bowl.
Within six weeks, there are enough worker bees to take over the food gathering responsibilities, so the queen can stay in the nest and lay more eggs. The workers also care for the young bees, monitor the internal temperature of the nest and defend the colony against potential predators. Depending upon the species and food resources, bumblebee colonies will have ip to hundreds of individuals at their population peak.
Later in the summer, the queen begins to lay eggs of male bees and new queens, who will mate after emerging from the nest to begin the life cycle anew. Mating is the sole role of the male, but the new queens will carry his genes forward to the next year.
Most people know a black and yellow bumblebee when they see one. How many young children have been a bumblebee for the school play or Halloween? What I didn’t know is that there are approximately 50 species of bumblebees in the U.S., with 25 living in the Northeast.
Bumblebee species come in three varieties: short, medium and long-tongued bees. Some of the short and medium-tongued bee populations are doing quite well, but others, particularly the longtongued species, are in decline. There are multiple factors responsible for the steep decline in insect populations overall, including pesticides, climate change, non-native plants, loss of habitat and disease. But there are multiple ways humans can take action to protect them.
Dr. Robert Gegear, of UMass- Dartmouth, and his students have created an informative website and citizen science project called Beecology that focuses on the study of bumblebees. Check out the website at beecology.wpi.edu to learn how to identify different bumblebee species, determine what native plants are good nectar and pollen sources and read why pollinating insects are so important. The project started in Massachusetts, but has expanded into Rhode Island and other states. Anyone can download the app and begin adding data to the longterm study of bumblebees.
According to the site, insects that are pollinators have coevolved with certain native plants to the mutual benefit of both. The plant provides them with food in the form of nectar and pollen, but they provide the plant with a way to reproduce by moving pollen around from flower to flower. Humans and other animals rely on pollinators for many of the foods we eat. In my house, bumblebees are important because they pollinate tomatoes, raspberries, strawberries and blueberries.
Different bumblebees have evolved to feed on different plants. For example, flowers like bonesets, milkweed and bee balms are good nectar sources for short and medium-tongued species. Longtongued species, however, feed on flowers like turtlehead, spiked lobelia, blue flag and jewelweed. If you compare the shape and structure of flowers like milkweed and turtlehead, you will see why a bumble bee with a long tongue would prefer the latter.
When the queen bees emerge in spring, they need nectar for survival and pollen for reproduction. However, not all nectar and pollen producers are created equal. For example, early blooming pussy willows are a good source of pollen and nectar for the bees. Eastern redbud and American holly are good early nectar sources, but don’t provide the pollen needed for reproduction.
People, businesses and communities with gardens can do a lot for bumbles and other pollinators by being thoughtful about what they plant. It is important to find original strains of native plant species.
There are many cultivars of native plants sold in garden shops, but not much data on how much pollen and nectar these cultivars actually produce.
Use your power as a consumer and shop for original strains of native perennials, shrubs and trees. If you have a favorite garden shop, ask them to start carrying these original strains. They may have to start by growing them from seed, but most are growing their own plants anyway.
The Rhode Island Wild Plant Society is focused on preserving and proliferating native species. They have two annual native plant sales in May and June that are open to all.
Planting native does not mean you have to rip out everything in your garden and start over. At the Audubon Nature Center in Bristol, a beautiful pollinator garden was planted over the past three years. Then, the gardeners met Gegear and realized that they had not originally taken the importance of protecting the whole life cycle of bumblebees and other pollinators into account when planning it.
This year, the garden team resisted the urge to cut back the garden too early, because many insects lay their eggs in the stalks of plants over winter. Instead, they waited until there was a run of five days of warm weather to give the insects time to emerge. Then, as an extra precaution, the dead stalks were simply left on top of the soil.
Also, as funding becomes available, Audubon is replacing non-native plants and native cultivars by purchasing original strains from trusted sources like the Rhode Island Wild Plant Society and the Native Plant Trust in Framingham, Massachusetts. The team is also growing their own plants from seed at the Rhode Island Veterans Community greenhouses in Bristol.
Over time, the plants in the Audubon garden will offer a variety of pollen and nectar sources to pollinators no matter how long their tongues are!