Meet Lepidopterist Alma Solis

Dr. Alma Solis is a research entomologist at the Systematic Entomology Laboratory (SEL) of the Agricultural Research Service (U.S. Department of Agriculture) and is located at the National Museum of Natural History, Smithsonian Institution, where she is curator of various moth families. At UT Austin, she was an undergraduate until 1978, and then continued her graduate work. In 2016, she was President of the Systematics, Evolution and Biodiversity section of the Entomological Society of America, and in 2018, she was honored as a Fellow of the Entomological Society of America. She is a 2019 UT Austin Distinguished Alumnus. 

We interviewed her to learn more about her start in the field of lepidopterology, and how people can support moth populations in their own yards.

What got you interested in moths and butterflies?

I was a graduate student of Dr. Larry Gilbert in the Zoology Department. I wanted to work on pollination biology, but he said that for a Master’s research project, it would be hard to quantify. He suggested I work on leaf mining moths. He was inspired by Paul Opler’s work on leaf mining moths whose larvae feed on oaks in California. I then proposed to work on leaf mining moths on three tree species, hickory, maple, and sweetgum, in a cloud forest in northeastern Mexico and compare them to those feeding on same species of trees in northeastern United States. During this study, my interest expanded to other moths.

Your field, broadly speaking, is on the biodiversity of moths. A lot of people don’t think about moths the same way as they might butterflies. Why should that change?

There is more interest in butterflies because people can see them during the day. This should change because there are more moth species on the planet than butterflies (there are about 140,000 species of moths and only about 19,000 species of butterflies), but both are significant organisms in ecological webs. Every life stage, eggs, caterpillars, and pupae (or chrysalis), provides food for other organisms such as birds, bats, reptiles, and other arthropods. Caterpillars decompose leaves on trees for our soil by feeding on them.

Adult moths can be general pollinators, usually at dusk, although the ones that have been studied have very intimate relationships with the plants they pollinate, such as the senita moth and the senita cactus. They also provide food for bats and other night flying animals. The most successful groups of moths have developed tympanal organs or ears to “hear the bats” and evade them.

But moth caterpillars can have a direct impact on humans because they are so successful as pests of crops that humans eat, like corn or wheat (and why I work for the US Department of Agriculture). The caterpillars in my group can be direct pests of stored food in people’s homes, such as flour, or seeds, such as nuts, in pantries. On the plus side, some species in my group can control plants that have become invasive in different parts of their native habitat, for example, fern-feeding moths to control the Old World Climbing Fern in the Everglades. Some moth caterpillars are a double-edged sword, like the cactus moth for the control of cacti in many parts of the world, but most recently became an invasive species in the United States and is now found in Texas.

You spent a few months completely alone in the cloud forest of Rancho del Cielo, researching leaf mining moths and their host plants. Why did you choose this spot for research?

I am from south Texas where I was most acquainted with fields of crops, such as tomatoes, melons, or grapefruits. I was introduced to Rancho del Cielo, a cloud forest in northeastern Mexico just 260 miles southwest of where I grew up in Brownsville, Texas, during my freshman year at Texas Southmost College. This was not just a forest, but a cloud forest where the clouds came in, and left every leaf glistening. I could feel my face tingling with the minute droplets of water. I had never seen such tall trees, over 100 feet tall, or bromeliads, or ferns in such abundance. This is where my interest in the biological world evolved. Even after I transferred to UT Austin, I would go back as a volunteer. I felt comfortable and safe. I knew all the trails and how the buildings functioned. So later when I was looking for a location to conduct fieldwork, this seemed very natural.

How was the experience of being alone there for you? What were the challenges? Any amazing memories you wish to share?

The first three days were tough. Every noise was something. I couldn’t sleep and I slept during the day. I couldn’t go on like this and decided to do something about it. After the third day I went outside the cabin where I was sleeping and found every little noise-making structure, a branch hitting the roof, a loose piece of aluminum, squirrels running across the roof, acorns dropping on the roof, etc. Some of the sounds were bats living in the roof between the aluminum and the wood of the cabin.

There are two ways to collect moths at night. One is to put out a trap before it gets dark and then pick it up in the morning. The other is to set out white sheets with special lights to attract the moths. You learn to dodge the bats and eventually you forget about them. Some of the larger moths, such as the Black Witch moth, have spurs on their legs that can be painful when they attach to you. For my research, I mainly used traps, but the sheet collecting was more interesting because you can see the wide variety of moths that come to the lights, you can pick and choose which ones are of interest. One of the most terrible things that happened was that a moth found its way into my ear canal. There was no one else around to use a forceps to pull it out. I couldn’t poke at it myself for fear of puncturing my eardrum. I had to let it live, but the sound of a flapping moth in your ear canal is horrible. I had to kill it by putting alcohol in my ear. It stopped moving, but then I had to wait for the moth to decompose and come out in pieces.

One of the more amazing events was when the vehicles left the compound in the first day, many of the usually difficult birds to see, flocked into plain sight. There were Blue crowned mot-mots, Mountain trogons, and woodcreepers, for example, perching within a few feet of me until they realized I was there.

With spring starting, (at least here in Austin), how can people during these months of spending more time at home see moths in their backyard? What resources can we point them to for identifying and learning about them?

If you live near a wooded area, you can leave your porch light on and then go out and see what is on your wall. Lepidopterists always inspect walls. You can join groups that have excursions to see moths, such as the Austin Butterfly Forum (I am proud to say I am a member). Shortly before the pandemic, I was a speaker at Mothapalooza in Ohio. I was amazed to see many people come together at a state park to put out their sheets and lights just to see moths. There are books for the identification of moths and their caterpillars, websites online like the Moth Photographers Group, and of course, now there is iNaturalist, a site where folks post pictures of moths and other organisms so that they can be identified by others.

How can people support moth populations in their own neck of the woods?

One of the first things my husband and I did when we bought a home with property was to plant a butterfly garden. You can hear about our garden in an NPR interview: “Rare Specimens: An Unusual Matchup in Entomology.” We planted trees and shrubs, including a tiny meadow, that adult female moths and butterflies can lay eggs on, and that the caterpillar can feed on when it hatches. There are native plants for your area that native larvae can feed on and thrive. You can plant them in pots. Many folks buy butterfly weed plants to attract the adults, but the female butterfly and moths can’t lay eggs on these non-native plants.