Pollinator That Doesn’t Get Enough Spotlight: Hawk Moths

When we talk about pollinators, we can quickly say butterflies and bees. And while I absolutely adore bees, especially bumblebees (they look so fluffy I can’t), there are other insects that do this role. We’re going to talk about hawk moths first.

I don’t particularly like moths (except the bigger ones, probably because as a kid my parents and siblings kept on telling me that small moths can go into my ear canals and make me go deaf. Families, am I right?), but I don’t mind them as well. Therefore, I don’t know much about them.

Apparently, hawk moths are known for their ability to travel incredible distances and for their extremely long proboscises (straw-like tongues from which they guzzle nectar).

When a hawk moth drinks from a flower, the proboscis picks up pollen, which can be spread to flowers farther than 29 kilometers away as the moth travels along its feeding route.

Hawk moths and their matches

This species, which is closely related to butterflies, don’t pollinate food crops. That’s why they’re less popular than insects which help the farming industry and we don’t hear that much of them.

Regardless, these moths are important for the survival of many native plants. Without them, these plants will disappear and it can permanently change diverse and unique habitats.

Interestingly, according to Smithsonian’s curator Dr. Robert Robbins, some plants and hawk moths evolved to prefer each other. For example, Lepidoptera, which are plants with long flowers that favor the moths because of their long tongue-like proboscises.

With this, moths with shorter proboscises can’t access the flower’s nectar, so it’s a win for hawk moths. Meanwhile, the plant wins because its pollinators are likely to visit the same kinds of plants when they make their next feeding stops. And, this mutualism increases the plant’s chances of successful pollination.

Successful pollinations like these are important because many plants that hawk moths feed on are endangered, suffering from deforestation and tourism. For instance, the red-flowering Puerto Rican higo chumbo cactus lives on three small islands off the coast of Puerto Rico. To survive, it needs pollinators that can fly across the ocean.

Hawk moths, which are large, strong, and can fly long distances across island chains, become the perfect higo chumbo cactus. The moths also pollinate the spiky Egger’s century plant, an imperiled species of agave that survives in small, scattered populations on St. Croix of the Virgin Islands.

“The populations of these plants are getting more fragmented. If the moths continue to focus on certain plants, they can actually maintain connections between these very fragmented populations,” said Dr. Gordon Smith, an entomologist at the University of California, Riverside.

Studying hawk moths

Hawk moth (Ambulyx pryeri pryeri) from Sabah, Borneo. Photo by Charles J Sharp Wikimedia Commons
Hawk moth (Ambulyx pryeri pryeri) from Sabah, Borneo. Photo by Charles J Sharp Wikimedia Commons

Scientists have been studying pollen stored on hawk moths’ proboscises so that they can understand roughly where each moth has been. Then they can potentially use this data to chart how native, endangered plant populations have decreased overtime.

“We can take these hawk moth specimens from the 1900s and see what plants they were visiting in their communities when they were alive and around,” said Smith.

The Smithsonian’s National Museum of Natural History has the second largest hawk moth collection in the world. The collection contains moths from as far back as 1895, allowing entomologists and botanists to study the relationship between insect and plant in different decades. In fact, the museum has several specimens out currently on loans for scientific research.

“Each individual insect is a data point. When people study the specimens, they unlock this dark data. When you collect any type of specimen, especially entomology specimens, you can track diversity and population dynamics over time,” said Jessica Bird, the collections information manager for the Entomology department at the museum.

In danger too

Just like all pollinators, hawk moths are threatened by climate change, invasive species and pesticides. Now, once a species is extinct, its co-dependent plants will likely disappear too.

For example, entomologists suspect the highly elusive Fabulous Green Sphinx Moth of Kaua’i, Hawaii is gone, leaving the critically endangered vulcan palm with no natural pollinators.

Now, the palm has disappeared from the Hawaiian wild. You can find them as an ornamental house plant, but it’s gonna be a super rare thing to see them in the wild again.

Even though human interference has harmed this species, they’re still more resilient than fragile crop-pollinating insects like European honeybees. Their ability to fly long and hard, as well as their lengthy proboscises, makes them crucial for many at-risk plants’ survival.

“Hawk moths tend to move pollen farther than bees or birds. That helps plant populations remain viable in the face of habitat degradation,” said Dr. Robert Raguso, a biologist at Cornell University and one of Smith’s collaborators.

The pollinators are a safeguard for many habitats. Without hawk moths to visit native, endangered plants, we will no longer see rare and beautiful flowers in the wild. Even worse, ecosystem diversity could decline.

Beware of wasps (sometimes)

young female paper wasp (usually mistaken for yellowjackets). Photo by Alvesgaspar Wikimedia Commons
young female paper wasp (this species is usually mistaken for yellowjackets). Photo by Alvesgaspar Wikimedia Commons

As much as I don’t like wasps, I realize that they’re also important pollinators. And, they’re not all bad. Some small wasps like trichogramma and braconid wasps don’t build nests and can’t sting, but they eat caterpillars, leaf skeletonizers, pecan casebearers and other pest insects.

Wasps that are the most helpful are the braconids because they don’t sting people but they can kill pests. Some people want to protect them by avoiding even the organic pest-control products because they commonly hurt many more beneficials than the targeted pests.

Paper wasps and red wasps are among the more dangerous ones but they’re still beneficial because they eat pest insects and feed them to their young. They will sting us if we’re meddling around with their nest. Just know that paper wasps are rarely aggressive, while red wasps’ stings are more painful and they’re more ready to attack.

Additionally, cicada killers (sphecius speciosus) that seem so menacing (look at their pointy rears ugh) are apparently less dangerous. They sting only when they’re grabbed. If you can see hole in the ground and see them flying around at your knee level, it might be their nests and they’re warning you to stay away.

Just… just stay away from Texas yellowjacket. They’re horrible. Yes they play a role in the ecosystem and whatnot, but they’re super aggressive so just run once you see them. If they have a nest around your house, let the professionals handle them.




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