The truth about hummingbird pollinators: are they better than bees?

Inside: We recognize hummingbirds as potent pollinators. But how does a bird pollinate flowers when it doesn’t have pollen-collecting equipment like a bee?

How do hummingbird pollinators compare with bees?

Beekeepers spend a lot of time marveling over the colorful pollen loads their bees collect. Not only do they harvest pollen directly from flowers, but they groom it from their furry bodies, bodies equipped with pollen-attracting electrostatic charges. It seems nature designed bees with pollination in mind.

A few colorful facts about hummingbird pollinators

Although they are both hairless and basketless, hummingbirds are premier pollinators. Hummingbirds live only in the western hemisphere, mainly in the equatorial belt. Despite their limited distribution, the group comprises over 365 species. Only 15 species live permanently in the US, but nine more occasionally wander over the southern border.

Most hummingbirds are small. The smallest, the bee hummingbird, is about the size of a bumble bee, hence the name. The largest, the sparrow-sized giant hummingbird, approaches the weight of 4 US nickels. Hummingbirds living in the US include the Ruby-throated hummingbird (common in the east), Anna’s (native to the west coast), Rufous (north to Alaska), Costa’s (Sonoran and Mojave deserts), and the Blue-throated (the largest US species).

How to recognize a hummingbird

Even if you’ve never seen a hummingbird, they are easy to recognize. Their bodies are short, but sleek, beginning with a long, slender bill. They often have iridescent feathers that glimmer in the sunshine as they dart from place to place at breathtaking speeds. However, despite their speed, they can stop short and hover in mid-air. And for good measure, they can even fly backward.

Although their name describes the sound made by their fast-moving wings, I don’t think of it as a hum as much as a threat. Who hasn’t ducked in fear when an unexpected hummer surveilled your body as a potential food source? They remind me of giant mosquitos.

How hummingbirds pollinate flowers

Hummingbirds drink loads of nectar, something they find at the base of certain flowers. As a hummingbird reaches its long, narrow beak into the tube of a flower, it can dislodge pollen from the anthers of the flower. Some of this sticky pollen adheres to the face and beak of the bird.

When the hummingbird goes to the next flower, some of the pollen may rub onto the flower’s stigma, causing pollination. When we watch hummingbirds hover, they often seem far from the reproductive parts of the flowers. We may think, “That’s not going to work.” But it does, and the whirring wings have a lot to do with it.

The rapidly beating wings cause air turbulence that makes some of the pollen grains go airborne. The grains may land on other parts of the bird’s body, or they may float in the air, eventually landing on another flower of the same type, causing pollination.

Hummingbird feathers have many tiny branches called barbs. The barbs are further divided into smaller branches called barbules. These little hooks hold the feathers together, but they also snag pollen grains and carry them from flower to flower. When the pollen rubs onto the stigma of a similar flower, pollination occurs.

How much pollination can hummingbirds do compared to honey bees?

The Audubon Society claims that a hummingbird can visit up to 2000 flowers per day. Estimates vary, but the typical honey bee can visit somewhere between 1000 and 5000 flowers per day, depending on planting density, flower type, weather, distance traveled, and so on. A solid average number is about 1500 flowers per day, less than a single hummingbird.

But the outstanding thing about honey bees is the immense size of the colony. In a small colony of say 20,000 bees, 30 percent (6000 bees) may be foragers. So even if a typical forager visits a mere 1000 flowers per day, you need to multiply that by 6,000, which gives you 6,000,000 visits per day for that one colony.

Now assume you have a large colony of 60,000 bees pollinating small, closely spaced flowers. Even if only 30 percent are foragers, you could have 18,000 foragers pollinating up to 5000 flowers per day. That’s 90,000,000 for the colony. Ninety million flowers in one day!

Plants they share and plants they don’t 

Of course, hummingbirds and bees often choose different plants. Some they enjoy in common, such as anise hyssop, zinnia, and geranium. But honey bees seldom visit flowers with long tubes, such as foxglove, columbine, and daylily. That means the hummingbirds are doing vital work honey bees cannot.

In regions with many hummingbirds, such as the tropics, the amount of pollinating the hummers do is huge. The Audubon Society estimates that hummingbirds pollinate about 8000 species of plants in the Western Hemisphere.

What flowers attract hummingbirds?

A pollination syndrome is a set of flower characteristics that attracts certain types of pollinators. By looking at a flower’s traits, you can often predict what type of pollinators will visit the plant.

The hummingbird pollination syndrome is called ornithophily. That hard-to-pronounce word describes the flower characteristics that attract hummingbirds (and some other birds). Hummingbirds like:

• Large flowers
• Vividly colored red, pink, orange, and yellow petals
• Flower tubes (corollas) that are long and slender
• Petals that are leathery and not easily damaged
• Anthers and stigmas (reproductive flower parts) that extend outside of the corolla
• Flowers that secrete lots of nectar
• Flowers without odor

Bees have a pollination syndrome too, called melittophily. When a flower meets the requirements of both hummingbirds and bees, you will see them share those flowers. Otherwise, each group of pollinators goes its own way—one of nature’s ingenious ways of limiting competition between species.

Frequently asked questions

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