Hummingbirds and bees are both important pollinators for flowers, but hummingbirds have several advantages that make them more effective at pollinating than bees in many cases. Here’s a closer look at why hummingbirds are often superior pollinators.
Flight Abilities
One major advantage hummingbirds have over bees is their flight ability. Hummingbirds can hover in place and fly backwards, unlike bees. This allows them to efficiently access all parts of a flower to collect nectar and pollen.
Bees cannot hover or fly backwards. They must land on a flower and crawl around to feed. This limits their access to pollen compared to hummingbirds that can maneuver to all areas.
Additionally, hummingbirds have thinner, longer beaks than bees. Their slender beaks allow them to reach deeper into tubular flowers to access nectar that bees cannot. Their long beaks also come into contact with more pollen.
Flower Specialization
Many flowers rely specifically on hummingbirds for pollination. These flowers, such as columbines and fuchsias, are specially adapted to hummingbirds.
Their shape complements the hummingbird’s long beak and hover feeding. They are often brightly colored red, orange or pink to attract the birds. Their nectar is perfect for hummingbird nutritional needs.
Bees are not specifically adapted for these hummingbird flowers. The bees are often unable to feed from them properly. So hummingbirds are superior pollinators for the plants that specialize on hummingbird pollination.
Energy Use
Hummingbirds have extremely high metabolisms and require large amounts of food energy in the form of nectar. Bees have lower energy demands than hummingbirds.
This means hummingbirds visit up to 1,000 flowers per day seeking nectar, whereas bees may only visit 5-100 flowers per day. The more flowers a pollinator visits, the more pollen it spreads from flower to flower.
So while visiting a garden, a single hummingbird may impact the pollination of far more plants than a single bee due to its greater energy needs.
Territory Range
Hummingbirds cover wide territories each day seeking nectar to fuel their high metabolisms. A single hummingbird’s territory may extend over several square miles.
Bees tend to forage over much smaller areas close to their hive or nest. A single bee colony may only forage in an area within a few miles of the hive.
The wider territory range of hummingbirds means they can pollinate diverse plants across a broader geographic area than bees. This makes them important long-distance pollinators between fragmented habitats.
Specialization on Particular Plants
Bees tend to specialize on a few plant species or families for nectar. They learn to seek out the most productive flowers.
Hummingbirds are generalists and visit a wide diversity of flowering species. This makes them more effective at cross-pollination between different species of plants.
| Pollinator | Food specialization | Result |
|---|---|---|
| Bees | Often specialized on a few plant types | More self-pollination within plant species |
| Hummingbirds | Generalist, visit diverse flowers | More cross-pollination between species |
The generalist feeding of hummingbirds promotes more genetic diversity through cross-pollination between unrelated flower species.
Behavior While Feeding
Bees collect pollen on purpose and pack it into baskets on their hind legs. They deliberately gather pollen to take back to the hive to feed larvae.
Hummingbirds do not purposely gather pollen. They are after nectar. But plenty of pollen sticks to their heads and throats inadvertently while feeding.
Research shows bumblebees groom off 95% of pollen from their bodies while feeding at a flower. They do this to maximize the amount of pollen packed and taken back to the hive.
In contrast, hummingbirds do not groom while feeding. This means they carry more pollen grains on their bodies to the next flower.
Flower Structure Interaction
Flowers adapted to bee pollination often have anthers (pollen-producing structures) that are close to or rub directly on the bee’s body while feeding.
Hummingbird flowers have anthers located a bit farther away to account for the hummingbird’s long beak and head. This leads to more pollen accumulating on hummingbirds before transfer to the next flower.
Number of Visits Per Flower
Bees tend to spend more time per flower than hummingbirds. They crawl over the flower gathering nectar and pollen methodically.
Hummingbirds dart quickly into a flower, lapping up nectar with their long tongue. They spend only brief moments at each blossom before zipping to the next.
Spending less time per flower means each visit is more likely to deposit fresh pollen from a different plant. The shorter visitation periods of hummingbirds enhance cross-pollination.
Carrying Capacity
The small size of bees limits the amount of pollen they can carry between flowers. Their total pollen load may be a few thousand grains at most.
Hummingbirds are larger with more surface area on their beaks, heads, and bodies to carry pollen. They may transport between 5,000 to 100,000 pollen grains at a time.
This greater carrying capacity makes hummingbirds more efficient delivery vehicles for pollen transport and spread.
Migration
Most bees do not migrate long distances, remaining in the same general region year-round or seasonally.
Many hummingbird species are long-distance migrants between breeding and wintering grounds. Ruby-throated hummingbirds migrate over 1,500 miles between Canada and Central America.
This migration allows hummingbirds to pollinate plants over a vast geographic range. They transport pollen between regions thousands of miles apart that bee pollination cannot bridge.
Climate Resilience
Hummingbirds are warm-adapted with higher temperature tolerances than bees. They can withstand hotter climates.
Bees fare poorly in extreme heat. Hot temperatures interfere with their flight muscles and ability to forage.
In areas with hot climates or seasons, hummingbirds may provide more consistent pollination. Bees are restricted during the warmest periods when hummingbirds still actively feed.
Pollination in Poor Weather
Bees avoid flying in wet conditions. Rain keeps them confined to the hive, unable to pollinate flowers.
Hummingbirds are not deterred by light rain or drizzle. Their flight is adapted for maneuverability, allowing them to access flowers even in light precipitation.
This gives hummingbirds an advantage in pollinating during periods of intermittent rainy weather when bee activity is halted.
Flower Preference Overlap
There is substantial overlap between hummingbirds and bees in flower preferences. Many popular garden flowers, such as petunias, zinnias and salvias, attract both pollinators.
However, hummingbirds can access many flowers that bees physically cannot pollinate properly. Their flower preferences extend beyond bee favorites.
Having broader flower preferences means hummingbirds pollinate plants that bees fail to pollinate, increasing overall pollination services.
Number of Species
There are roughly 20,000 species of bees globally. Comparatively, there are over 330 hummingbird species.
The greater diversity of hummingbirds means they fill more niches and can specialize on certain flower traits and regions. This enhances their overall value as pollinators.
Pollen Digestion
While gathering nectar, hummingbirds inevitably ingest pollen. Research shows they digest some of this pollen to derive protein and nutrients from it.
Bees do not purposefully eat pollen. They consume nectar for energy but store pollen externally for larvae rather than digest it.
By digesting pollen, hummingbirds destroy those pollen grains rather than transferring them intact to other flowers.
This gives bees an advantage in the percentage of pollen that remains viable for plant fertilization after a floral visit.
Conclusion
In summary, hummingbirds have several advantages that make them generally superior pollinators compared to bees in certain situations:
- Exceptional flight maneuverability
- Specialized pollination relationships with some flowers
- Higher energy needs driving more frequent feeding
- Larger territory ranges
- Generalist foraging on diverse flowers
- Minimal grooming while feeding leading to more pollen transfer
- Greater carrying capacity of pollen
- Long-distance migration spreading pollen widely
- Functionality in hot weather
- Ability to feed in light rain
- Broader preference for flower types
However, bees also have some advantages, including purposeful pollen gathering and no digestion of pollen. The two groups complement each other. Having a diversity of pollinator species, including both hummingbirds and bees, improves pollination services for flowers and plant reproduction.
