The Hummingbird Moth, belonging to the genus Hemaris, is a fascinating insect often mistaken for a small bird due to its unique flight patterns. These moths are sometimes called clearwing moths because transparent patches appear on their wings when the scales shed shortly after they emerge from the pupa. Their robust, furry bodies and swift movements contribute to a remarkable example of visual mimicry. The diet of this insect changes completely as it progresses through its life cycle, requiring fundamentally different food sources for the adult and larval stages.
The Adult Diet: Fueling Flight
The adult Hummingbird Moth relies entirely on nectar, a sugar-rich solution produced by flowering plants, to power its active lifestyle. Nectar provides the simple carbohydrates necessary to sustain the moth’s high-energy flight, which involves wingbeats fast enough to create an audible hum. The adult moth consumes no solid food, foliage, or pollen.
They seek flowers offering substantial nectar rewards, often selecting those with a higher sugar concentration. These moths prefer specific shapes, such as tubular or deep-throated structures. This floral architecture ensures the nectar is accessible only to specialized pollinators, reducing competition. The high energy demand of their sustained hovering flight makes the selection of nectar-rich flowers essential for the adult’s primary functions: reproduction and dispersal.
The Larval Diet: Essential Host Plants
The larval stage, commonly known as a hornworm caterpillar, requires a diet consisting entirely of leaves from specific host plants, contrasting sharply with the adult diet. This stage is dedicated to growth, and the foliage provides the proteins and complex nutrients necessary for the caterpillar to rapidly increase its size and undergo metamorphosis. The female moth strategically lays eggs exclusively on the leaves of these host plants, ensuring the newly hatched larvae have an immediate food source.
The larvae feed on a limited range of plants, mostly within the honeysuckle family (Caprifoliaceae). Specific examples include snowberry and various species of honeysuckle. Some larvae also feed on plants in the rose family, such as hawthorn and certain cherry or plum trees. The host plant provides the nutritional building blocks required for the caterpillar’s transformation into the adult form.
Specialized Feeding Behavior
The physical mechanism by which the adult Hummingbird Moth acquires its liquid diet is highly specialized and is the source of its common name. The moth possesses a long, flexible feeding tube called a proboscis, which remains coiled tightly beneath its head when not in use. When the moth locates a suitable flower, this proboscis unfurls, allowing the moth to insert the tube deep into the flower’s nectary to siphon the liquid.
The moth maintains its position in the air by hovering directly in front of the flower, beating its wings rapidly and precisely to stay suspended without landing. This hovering allows the moth to move quickly and efficiently from one bloom to the next, maximizing its foraging time. This continuous, high-speed flight contrasts sharply with the feeding behavior of the larva, which simply chews and consumes large quantities of stationary foliage.