Everything You Wanted to Know About Bees and Other Pollinators

Take a walk in the summer, and if there are flowers in the neighborhood, you’ll probably see bees, busy buzzing around collecting pollen. We usually think of honey bees and bumble bees doing the pollinating, but look more closely: There are green bees, big bees, small bees—and other pollinators like butterflies and hover flies, too.

In fact, nearly 400 species of bees appear in Massachusetts alone, says Nick Dorian, A16, AG23, a graduate student in biology doing Ph.D. research on native bees. Dorian helped found the Tufts Pollinator Initiative, which seeks to educate the public about the benefits of these insects—and how we can help them.

Tufts Now spoke with Dorian to learn more about insect pollinators, get the inside dope on bees—no, not all bees make honey—and learn what we can do to help.

Tufts Now: Why should we care about pollinators?

Nick Dorian: Our world would be very different without insect pollinators like bees, butterflies, and beetles. They are really important for the reproduction of plants, which we benefit from in many ways, such as crops like apples, blueberries, pumpkins, and coffee.

Pollinating insects are the backbone of the ecosystem. They help wild plants reproduce. They make sure that there’s food for other critters, and that cascades throughout the ecosystem. For example, many songbirds depend on bee-pollinated plants to migrate.

Bees are by far the most important crop pollinators, but many animals that visit flowers are capable of helping plants reproduce. Some wasps are pollinators, as are hover flies, houseflies, moths, and hummingbirds.

How many kinds of bees are there?

There are nearly 400 kinds of bees in Massachusetts—and some 4,000 species of bees in North America. For every flower that’s around, there is almost certainly a bee that visits it.

“Pollinating insects are the backbone of the ecosystem,” says Nick Dorian. Photo: Anna Miller

When most people think of bees, they think of honey bees, which live in hives with a queen and make honey. Honey bees were brought to North America by colonists in the 1600s, but there are hundreds of other native bees that have lived here for thousands of years. They don’t live in hives or make honey, but they are still excellent pollinators. Native bees live wild, without beekeepers.

There’s amazing variety. There are blue bees and red bees and green bees. There are bees that nest underground, that nest in the trees; there are bees that collect oils from flowers and there are bees that make their nests out of flower petals and feed their offspring pollen and nectar from flowers. There are bees that walk on water and others that sleep in flowers.

You don’t have to go far to find all this biodiversity. Sure, you can see incredible biodiversity in the tropics, but there’s also a lot of biodiversity in the middle of the city, if we just shift our focus.

Are all bees equally good at pollinating plants?

Honey bees are generalists, meaning they visit a wide variety of plants, but they are not great at pollinating any one particular plant. But there are many bees that specialize in a particular kind of flower. There are sunflower bees, for example, that far surpass the efficiency of honey bees as sunflower pollinators, but those sunflower bees would not be able to pollinate blueberries.

There are bees that only visit orchard flowers. They’re active in the spring when apples and plums need pollinating. There are blueberry bees that don’t really care about the apples, even though they’re blooming alongside the blueberry flowers—they only care about the blueberries.

This goes back to why we need biodiversity. Having a diverse set of bees ensures that there’s resilience built into our food system and our ecosystem.

Do you have a favorite bee?

The squash bee—I love it because it’s such a gateway into the world of wild bees. They are found in almost every vegetable garden in the greater Boston area—in fact, across most of eastern North America.

In the afternoon, you can peel squash flowers open and find sleeping bees inside. Without these bees, we wouldn’t have as many pumpkins and Halloween just wouldn’t be the same. We benefit from these bees and their tireless work.

How can someone tell what kind of bees they see on flowers?

It starts by making a habit of daily practice of noticing. Start by verbalizing what you see. Are the bees hairy? Golden? Are they big like a kidney bean or small like orzo? Are they slender or fat?

When you take away the pressure to make an identification and just focus on watching, you begin to notice that these bees all behave very differently. Some bees are a dark metallic blue. Others are bright green and land with their wings up. Other bees are really fuzzy, like bumble bees—you’ll see them late in the day after all the other bees have gone to rest.

There’s a whole wealth of online resources, too. There’s a community called iNaturalist where you can upload photos and experts like myself will help you identify them. We also have the Tufts Pollinator Initiative—we have ample guides online for helping you identify what you’re seeing.

Are most of the bees we see females, just like ants?

All the honey bees we see are females. Honey bees live in a hive with a single female queen and some 30,000 female workers. Male honey bees are produced only when new queens are produced and are rarely seen on flowers.

In contrast, since native bees don’t live in hives, we see both males and females. Males visit gardens to find mates, drink nectar, and take shelter. Females visit gardens in search of food—pollen and nectar—to bring back to the nest.

Unlike other animals, bees, ants, and wasps can control the sex of their offspring by either fertilizing or not fertilizing an egg, so it’s very intentional how many offspring a female makes and the sex of those offspring.

Males are often given less food because they just don’t need to be as robust or live as long as the females. The males have a very brief activity period. They mate and after that, the females stop being receptive and sometimes males are kicked away—the females will be like, “Hey, stop bothering me. I’ve got a nest to build.”

How can we help pollinators?

I have a little mnemonic that I use: SEEDS.

S stands for Spread native flowers, ones that our native bees have an evolutionary relationship with. These flowers, like sunflowers or goldenrods or asters, have lived in North America for thousands of years. I have a whole list of plants that are commonly available in nurseries and are bunny proof and great for supporting our native bees.

E is for Employ a life-cycle approach. Flowers feed adult bees, but for the other 10 months of the year, bees and other pollinators are out of sight. They are in their nests or developing. Delaying when you clean up your yard in spring until after May 1, when the temperatures have warmed, gives insects a chance to resume activity.

The second E stands for Eliminate pesticides. Tell the pesticide company, “No thanks.” Anything that kills a tick or a mosquito kills a bee.

D is for Discover what’s around you. People protect what they care about, and care about what they know. One of the greatest challenges facing pollinator conservation is that people usually don’t like insects. But insects can spark your curiosity, which starts by taking the time to notice them.

S is for Spread the word—I say it takes a hive to do this work. I encourage everybody to share what they know about pollinators with others—become an ambassador for bees.

What are you studying for your Ph.D.?

I focus on the ecology of a type of solitary bee called cellophane bees. They are blueberry specialists, meaning they get all of their nutrition from blueberry flowers. I noticed that females produce offspring that develop in different amounts of time.

Adults emerge from underground nests in spring, feeding exclusively on blueberry flowers that peak in early May in Massachusetts. Then they build new nests, and the next generation develops underground out of sight until the following spring. What’s intriguing is that some of them emerge one year later—as the next season of wild blueberry plants bloom—but others wait a full two years before emerging.

It’s like a diversified stock portfolio—a bee with a diversified nest. As our environment’s becoming increasingly more unpredictable, I’m interested in whether this allows bees to cope, buffering them against a particularly bad year.