There is a unique insect that has characteristics resembling both a bee and a hummingbird. This interesting creature is called a hummingbird moth.
Hummingbird moths are insects that belong to the Sphingidae family. They are also sometimes referred to as hawk moths or sphinx moths. There are over 1,400 known species of hummingbird moths worldwide, with around 200 species native to the United States and Canada.
Hummingbird moths get their name from the fact that they share similarities with hummingbirds. They have the ability to hover in front of flowers and feed on nectar using their long proboscis which works like a hummingbird’s beak. Their wings also beat rapidly like a hummingbird’s up to 70 times per second.
Despite resembling tiny hummingbirds, hummingbird moths are more closely related to butterflies and silkworms. Like all moths, they go through a complete metamorphosis with four life stages – egg, larva, pupa, and adult. The larvae are worm-like caterpillars that molt several times as they grow. They often feed on plant leaves.
So while they display some hummingbird-like qualities, hummingbird moths are very much insects. But their unique attributes that blend characteristics of birds and insects is why they have captured people’s fascination.
Physical Appearance
Hummingbird moths have some distinctive physical features that contribute to their resemblance to hummingbirds.
In terms of size, they are pretty small for moths but still much larger than bees. Hummingbird moth species in North America have wingspans ranging from 1.5 to 6 inches. Their bodies are about 2 to 3 inches long. So they are closer in size to hummingbirds than bees or other pollinating insects.
These moths have stocky, hair-covered bodies like bees. But unlike most moths, they are active during the day. Their wings are clear and can beat at high frequencies like hummingbirds.
One of the most notable features of hummingbird moths is their long proboscis. This straw-like tongue can extend to reach nectar at the bottom of long tubular flowers. When not in use, it coils up under the head and thorax.
They have large heads and big eyes like hummingbirds. Their antennae are thick and tapered.
Hummingbird moths exhibit cryptic coloring with patterns that provide camouflage. For example, many species have brown, grey, or greenish bodies with streaks and patches of iridescent colors.
Overall, while they may look bee-like up close, in flight their shape, wing movements, and feeding behaviors make them resemble tiny hummingbirds.
Feeding and Behavior
Like hummingbirds, hummingbird moths feed on flower nectar. Their long proboscis allows them to obtain nectar from tubular flowers that bees and other insects cannot. They prefer flowers with higher sugar concentrations in the nectar.
Some favorite nectar sources include honeysuckles, petunias, lilacs, columbine, bee balm, and trumpet vines. Adults do not eat – they rely solely on nectar for nutrition.
While feeding, they beat their wings rapidly to hover in front of flowers. They can fly forwards, backwards, and upside down. This aerial agility allows them to reach nectar even in tricky spots.
Hummingbird moths exhibit territorial behavior. It is common for them to chase other insects or even hummingbirds away from flowers and feeding areas. They are active during daylight hours, typically early mornings and late afternoons.
During the night, they go into torpor to conserve energy. This involves entering a sleep-like state and lowering their metabolic rate. They may wedge themselves into tree bark crevices or holes in the ground to sleep.
Differences from Bees
Despite some similarities in appearance, hummingbird moths display very different feeding behaviors compared to bees:
- Bees chew and swallow both nectar and pollen from flowers. Hummingbird moths only drink nectar.
- Bees have chewing mouthparts to consume pollen. Hummingbird moths have a sucking proboscis.
- Bees intentionally collect pollen during feeding to take back to the nest. Hummingbird moths do not purposefully gather pollen.
- Bees have specialized structures to enable pollen collection. Hummingbird moths do not have these structures.
- Pollen sticks to hummingbird moths incidentally during feeding. But they do not eat it or feed it to larvae.
So while hummingbird moths may get coated in pollen while drinking nectar, they do not have the same pollen feeding and gathering behaviors that bees do.
Life Cycle
Hummingbird moths undergo complete metamorphosis with four life stages: egg, larva, pupa, and adult. After mating, adult females lay eggs on the leaves of host plants.
Eggs
The eggs are very small, spherical or ovoid. They are pale green, yellowish, or translucent white. The eggs hatch within 3 to 10 days depending on temperature and species.
Caterpillars
Hummingbird moth caterpillars are plump and smooth-skinned. They have a horn on the rear end which shrinks as they molt and grow. Caterpillars go through 5 to 6 instars where they shed their exoskeleton. Each instar lasts 1 to 2 weeks. Newly hatched caterpillars are only a few millimeters long but can grow up to 2 inches long when mature.
Caterpillars are voracious eaters. They feed on leaves of host plants and sometimes flowers and seeds. Some common host plants are:
- Honeysuckles
- Viburnums
- Willows
- Cherry trees
- Morning glories
- Hawthorns
The caterpillar stage typically lasts 2 to 6 weeks depending on environment and species.
Pupa
In the pupal stage, the caterpillar transforms into the adult within a protective silk cocoon. The cocoon is attached to a stem or leaf of the host plant or hidden near the ground. Pupation lasts 1 to 3 weeks before the adult moth emerges.
Adult
Once the adult moth emerges from the pupa, its only goal is to reproduce. Adults live for around 5 to 10 days. They do not eat anything besides nectar. Females emit pheromones to attract males for mating. After mating, females lay eggs and the cycle repeats.
Some species migrate while others overwinter as pupae. There are typically 2 to 3 generations per year in temperate climates.
Types of Hummingbird Moths
There are many different varieties of hummingbird moths across North America. Some of the most common include:
White-lined Sphinx Moth
Named for the white stripes along its body. Widespread throughout the United States and southern Canada. Greenish-brown coloration provides good camouflage against bark and leaves.
Nessus Sphinx Moth
Identified by its distinct pink and olive coloring. Found across western North America. Adults feed on nectar from flowers like larkspur and penstemon.
Five-spotted Hawkmoth
This species lives throughout eastern North America. It has transparent gray wings with 5 small pink spots on the hindwings. Drinks nectar from primroses and phlox.
Bumblebee Hummingbird Moth
Native to southwestern states like California, Arizona, and New Mexico. Has distinct black and yellow striping like a bumblebee. Feeds on nectar from plants like penstemons, sages, and mints.
Snowberry Clearwing Moth
Found across North America wherever its host plant, snowberry, grows. The larvae feed on snowberry leaves. Adults drink nectar from phlox, lilacs, honeysuckle and other tubular flowers.
Ecological Role
Although they don’t deliberately pollinate flowers, hummingbird moths play an important ecological role as pollinators. As they move from flower to flower feeding on nectar, pollen grains stick to their furry bodies and are transported to other blooms.
Certain flower species are reliant on hummingbird moths for pollination such as penstemons, columbines, and orchids. Their long proboscis allows them to reach nectar that other insect pollinators cannot.
Research indicates hummingbird moths can be just as or even more effective than hummingbirds at pollinating some plant species. Their hairy bodies and rapid wingbeats make them efficient accidental pollinators.
By pollinating wildflowers across North America, hummingbird moths help maintain plant biodiversity and healthy ecosystems. They pollinate plants that serve as important food sources for other wildlife.
Hummingbird moths are also an essential food source. Their nectar feeding benefits flowering plants, while larvae provide food for birds, small mammals, and other insect predators.
Threats and Conservation
Most hummingbird moth species are currently not considered threatened or endangered. But they do face some key threats to monitor:
- Pesticide use – chemicals applied in gardens, parks, and agricultural areas can be toxic if pollen covered in residues is consumed.
- Habitat loss and degradation due to human land use changes.
- Reduced availability of host plants, nectar plants, and flowering sites.
- Invasive plant species that do not provide good habitat and nutrition.
- Extreme weather events and climate change affects from drought to severe storms.
There are some measures that can be implemented to help conserve hummingbird moth populations:
- Reduce or eliminate pesticide use in gardens and landscapes.
- Protect areas with native vegetation that provide nectar sources, larval host plants, and nesting sites.
- Plant pollinator gardens with suitable flowers for nectar and larval host plants that bloom sequentially over seasons.
- Contribute sightings and population monitoring data to inform research and conservation efforts.
Conclusion
Hummingbird moths are a fascinating type of insect that possess some traits characteristic of birds as well as bees. While they may resemble tiny hummingbirds as they hover and feed on flower nectar, they are actually a moth species.
Key aspects that differentiate them from bees include their lack of pollen feeding and collection, sucking proboscis, and complete metamorphosis life cycle. But their role as accidental pollinators, especially for some deep tubular flowers, can be just as critical.
There are over 200 species found across North America that come in a rainbow of colors. Continued research and habitat conservation can help protect these unique pollinators into the future.
So next time you spot what looks like a tiny hummingbird fluttering among your garden flowers, take a closer look – it just might be one of these amazing hummingbird moths!
