11/02/2026
It's beginning to feel a lot like fall which means it's time for a passionate plea for everyone to LEAVE THE LEAVES!
Leaves are not litter, they're a natural component of a healthy, functioning ecosystem that we've been taught to view as an inconvenience. So this November, we're going to be challenging our brains to think of 'leaf litter' not as trash to be bagged but as leaf debris that harbors little lives --- or free compost, at least.
Each week, we'll post an overview of one of the native wildlife species that rely on fallen leaves and debris (think twigs and sticks and spent flower foliage, oh my!).
*Quick note; we always recommend removing leaves from hard surfaces like sidewalks or pavers (to reduce slip risks). If you can't leave them where they fall, carefully transplant them somewhere else. Please, pleaaase don't burn them, mow them, or bag them up to throw them away.
Today, we're going to take a look at the most common "clearwing" species in the eastern United States - the Hummingbird Clearwing (Hemaris thysbe). This sphinx moth looks like a hummingbird by happenstance (aka convergent evolution) and mimics a bumblebee on purpose as predator protection (aka Batesian mimicry).
Although the moths are diurnal (active during daytime), they're most frequently noticed at dusk and dawn on sunny days. This low light only contributes to their misidentification as hummingbirds. But why else did they get the common name "hummingbird moth?" Well, their wings produce the same iconic humming noise. Hummingbird wings typically beat 70 times a second; hummingbird moths, on the other hand, beat their wings an average of 85 times a second.
Their speed and ability to harvest nectar while hovering are excellent predator protection, making them an efficient pollinator. They're especially crucial for pollinating twilight or night blooming flowers. They help maintain the biodiversity and health of the various ecosystems they live in by visiting a wide range of plant species that are often missed or under-visited by daylight pollinators.
Adult moths harvest nectar from a wide range of flowers, particularly ones with long floral tubes due to their long tongue. They're known to visit honeysuckles (Lonciera spp.), beebalms (Monarda spp.), clovers (Trifolium spp.), Phlox spp., thistles (Cirisium spp.), and vetches (Vicia spp.).
Larval host plants for the caterpillars include honeysuckle (Lonicera), snowberry (Symphoricarpos), hawthorns (Crataegus), cherries and plums (Prunus), and members of the rose family (Rosaceae). The eggs are tiny, round, and typically green; they're laid on the underside of plant leaves. This is where the leaf debris comes in.
Clearwing caterpillars pupate over winter in a thin cocoon. Cocoons are formed after the caterpillars hide themselves under the fallen leaves and other debris that makes up the leaf litter layer. The leaves act as camouflage, offering a measure of protection against predation and winter weather. So let's leave the leaves and see more hummingbird clearwing moths next spring!
