Hummingbird moths are a group of moths that belong to the Sphingidae family. They are sometimes called “hummingbird clearwing moths” or “sphinx moths”. These moths get their name because they look and act very similar to hummingbirds when feeding on flowers.
One particular type of hummingbird moth that is well known for resembling a bee is the snowberry clearwing moth (Hemaris diffinis). This is a medium-sized hummingbird moth found in many parts of North America that has yellow and black stripes on its body, making it look very bee-like. In this article, we will discuss more about snowberry clearwing moths and how they imitate bees.
What is a snowberry clearwing moth?
The snowberry clearwing moth (Hemaris diffinis) is a diurnal moth that belongs to the Sphingidae family of moths. Some key facts about snowberry clearwing moths:
- Native to North America, found from coast to coast and up into Canada.
- Gets its common name from one of the host plants the caterpillars feed on, the snowberry bush.
- Wingspan reaches 1.5 – 2 inches across when fully grown.
- Has a stout, fuzzy body that is black and yellow striped, resembling a bumblebee.
- Flies low to the ground and hovers in front of flowers while feeding, like hummingbirds.
- Found in open fields, meadows, gardens, and forest edges.
- Adults feed on nectar from tube-shaped flowers like honeysuckles and penstemons.
- Caterpillars feed on snowberry, honeysuckle, viburnums and other shrubs.
So in summary, the snowberry clearwing is a medium-sized moth native to North America that mimics bumblebees in both appearance and behavior. Their unique look and flight habits contribute to this clever disguise.
Why does the snowberry clearwing moth look like a bee?
There are a few key reasons why the snowberry clearwing moth has evolved to resemble a bee:
Mimicry
The black and yellow striped body of the snowberry clearwing is an example of mimicry. By looking like a stinging bee, the moth aims to deter potential predators who want to avoid being stung. This provides protection from birds and other animals that may otherwise eat the moth.
Feeding Habits
Like bees, the snowberry clearwing moth feeds on nectar from flowers. Their body shape and long proboscis (tongue) allows them to extract nectar while hovering near the blooms. This bee-like feeding behavior further enhances the illusion that they are bees, not moths.
Pollination
It is thought that the bee-like appearance helps snowberry clearwings integrate themselves within flower ecosystems along with bees. Flowers may not distinguish between the moths and bees, allowing the moths to assist in pollen transfer as they feed.
Common Habitat
Both bees and snowberry clearwing moths thrive in similar environments like meadows and grasslands with plenty of flowering plants. Their shared habitat means predators will associate bees and the moths together due to encountering them in the same areas.
How does the snowberry clearwing moth imitate bees?
Snowberry clearwing moths are exceptional mimics of bumblebees. Here are some of the key ways they imitate bees:
Body Shape and Size
The snowberry clearwing has a thick, round body that is comparable in size to many bees. From a distance, their body shape helps them resemble a furry bee.
Color Pattern
The alternating yellow and black horizontal stripes on their abdomen look just like the patterns on bees. Some specimens also have a reddish-orange thorax which resembles the reddish hair found on some bumblebee species.
Flight Behavior
In flight, the moths exhibit a bee-like flight pattern. They hover in front of flowers while feeding and fly close to the ground. Their wings are partially transparent with dark veins and move very quickly, creating a blurry, buzzing effect reminiscent of bees.
Feeding Style
To drink nectar, the moths use their long, straw-like proboscis. They insert this into flowers to sip nectar just as bees do. The moths often land on flowers and move around to reach nectar, further imitating bee behavior.
Sounds
The rapidly beating wings produce a buzzing hum as the moths fly from bloom to bloom. This wing movement and resulting sound is very similar to the buzzing created by bee wings.
Are snowberry clearwing moths successful at mimicking bees?
Research has shown that the bee mimicry displayed by snowberry clearwing moths is effective against some predators, but not all.
Success Against Birds
Multiple studies have looked at how birds react to the moths. Results showed that certain bird species avoid trying to eat the moths due to their bee-like markings and flight patterns. This mimicry seems to be successful at deterring potential bird attacks.
Mixed Success Against Insects
Experiments with wasps and robber flies had mixed results. In some cases, the insects were deterred by the mimicry while in others they still attempted to prey on the moths. More research is still needed on how insect predators perceive the mimetic signals.
Not Effective Against Larger Predators
With very large predators, for example frogs, the mimetic signals seem to provide little or no protection. These predators likely rely more on motion and have less innate aversion to stinging insects. So for large predators, the moths are still detected as prey.
Mimicking the Right Bee Species Matters
Interestingly, mimetic success also depends on whether the clearwing moths match the abundant bee species in their local habitat. In areas with mostly tan-colored bees, the typical morph does poorly while the rarer tan-colored moth morph thrives. This highlights the specificity of this mimicry.
Do the snowberry clearwing moths benefit from looking like bees?
There are some clear benefits that snowberry clearwing moths gain by mimicking bees:
Avoidance by Predators
As discussed above, many insect-eating birds innately avoid bees to prevent getting stung. By looking like bees, the moths experience less attacks by avian predators that they would otherwise easily fall prey to.
Increased Feeding Opportunities
The bee-like appearance allows snowberry clearwings to feed undetected among flowers pollinated by actual bees. Rather than being chased away, they are able to sip nectar right alongside their models.
Added Pollination
The moths likely play a role in pollinating some of the flowers they visit. Their body hairs pick up and carry pollen, supporting plant reproduction. Plants in turn produce nectar that benefits the moths.
Access to Bee Environment
By mimicking bees, the moths can inhabit the same ecological niche. This grants them access to flowering meadows and other bee-dominated areas that may otherwise be too risky to exploit.
Mate Signaling
Unusual among moths, snowberry clearwings are day-flying. Researchers think the stripes help identify mates and facilitates mating opportunities while active in daylight.
What is the lifespan of a snowberry clearwing moth?
The snowberry clearwing moth has a relatively short adult lifespan compared to other moth species. Some key facts about their lifespan are:
- Adult moths typically emerge in late spring and live for 1-2 weeks.
- In warmer southern parts of their range, adults may emerge in early spring and live a bit longer.
- Most of their life is spent in the larval caterpillar stage, lasting 11 months or longer.
- Caterpillars hatch in early summer and feed on host plants until the following spring.
- The pupal stage, where the caterpillar transforms into the adult moth, takes about 25 days.
- Adults do not eat during their brief time alive. Their sole purpose is to mate and lay eggs.
In summary, the total lifespan of a snowberry clearwing moth is just over a year. But the adult moths that resemble bumblebees only live for a week or two before dying. Their efforts are focused on reproducing the next generation rather than longevity.
Where are snowberry clearwing moths found?
The snowberry clearwing moth can be found in many parts of the United States and Canada. Here is a little more detail on their geographic range:
- Found coast to coast in the U.S. from Maine to Washington state down to Florida and Texas.
- Most abundant in the northeastern states.
- Range extends north into the Canadian provinces of Quebec, Ontario, Manitoba, and British Columbia.
- Typically occurs in isolated colonies rather than scattered evenly across regions.
- Tends to thrive in montane and coastal areas over interior plains.
- Closely associated with the range of its snowberry host plants.
Within its range, look for snowberry clearwing moths in open meadows, fields, gardens, forest edges, and any habitat where nectar plants grow alongside its snowberry or honeysuckle host plants. They are most active during daylight hours.
What is the behavior of the snowberry clearwing moth?
The snowberry clearwing moth displays some unique behaviors compared to other moth species:
- Active during the day (diurnal) unlike most moths which are nocturnal.
- Feed exclusively on nectar unlike many adult moths that do not eat.
- Hover at flowers while feeding akin to hummingbirds.
- Frequently visits host plants like snowberry to lay eggs.
- Male moths patrol circuits in search of emerging females.
- Groom themselves often, rubbing legs over wings to clean.
- Males produce pheromones starting in mid-afternoon to attract mates.
- Perch with wings outstretched to thermoregulate in cool weather.
- May migrate short distances to expand range to new host plants.
The unique bee-like behaviors help the snowberry clearwing integrate itself within flower ecosystems and environment shared by bees and hummingbirds. Their daytime activity patterns centered around feeding and reproduction.
Do snowberry clearwing moth caterpillars also look like bees?
Unlike the adults, snowberry clearwing moth caterpillars do not resemble bees. The larvae have a very different appearance:
- Smooth green body that tapers toward the back.
- diagonal white and yellow lines running down each side.
- Large reddish-brown head with two short horns.
- Grow up to 2 inches long when fully mature.
- Found singly on host plants like snowberry, honeysuckle, viburnums.
- Blend in well by resembling plant stems and twigs.
- Many freeze and thaw over winter while still tiny caterpillars.
- Voracious eaters, sometimes completely defoliating host shrubs.
The caterpillar stage lasts for most of the snowberry clearwing’s lifespan. Their green cryptic appearance helps them remain hidden from predators while feeding. Only the adult moths have specialized markings and behavior to mimic bumblebees.
Can you attract snowberry clearwing moths to your yard?
Here are some tips for attracting snowberry clearwing moths to your yard:
Grow snowberry and other host plants
Planting their preferred snowberry, honeysuckle, viburnum, or hawthorn host plants will draw in egg-laying adults. Be sure to choose native species.
Add nectar plants
Good nectar plants to include are bee balm, butterfly bush, phlox, verbena, and any tubular native wildflowers. Use native plants the moths are adapted to.
Provide habitat needs
Mow minimally and avoid pesticide use. Provide brush piles, log perches, and other natural elements. Open, sunny areas with some bare dirt are ideal.
Set up a ‘moth diner’
Use a hummingbird feeder to make a sugar-water moth diner. Add sliced oranges or bananas to provide nutrients.
Choose outdoor lighting carefully
Avoid bright lights that draw moths in and disrupt their natural behaviors. Use yellow bulbs and keep lighting minimal.
Install bee boxes or nesting sites
This can further reinforce the “bee zone” environment. The moths may investigate bee boxes, though they won’t use them directly.
Be patient
It make take time for snowberry clearwings to find and utilize new habitat. Mimicking bees takes them to all the right places!
Conclusion
The snowberry clearwing moth provides a fascinating example of how insect species evolve physical adaptations and behaviors to mimic other organisms. By resembling bumblebees in markings, flight, and feeding behaviors, the snowberry clearwing gains protection from certain predators, better access to flower nectar, and opportunities to mate. Although not a perfect mimic, this form of deception works well enough to provide an advantage to the moths where they co-occur with bees. With their unique lifestyle, snowberry clearwings showcase the remarkable diversity and adaptations found among moths and other insects.
