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OFFICE HOURS

Entomology’s Indiana Jones

Mark Hoddle travels the world to find and unleash the natural enemies of agricultural pests

By Jules Bernstein | Photos by Stan Lim

T here is a curious buzz in Mark Hoddle’s office. It is a figurative buzz, because of Hoddle’s enthusiasm for controlling damaging pests with their natural insect enemies. But the buzz, at least today, is also literal. The sound is coming from long-nosed black palm weevils, flying in circles while tethered to an insect merry-go-round of sorts. The contraption is designed to test how far weevils can fly before they get tired.

“They are remarkably strong fliers,” Hoddle said. “On average, they can go about 25 miles in a day — 90 miles if they’re feeling frisky.”

Given how far and how fast they can travel, there are fears they’ll attack and kill the iconic palm trees throughout Southern California and wreck date crops in the Coachella Valley. So far, they’ve been mostly confined to San Diego County, where they’ve already destroyed tens of thousands of palms. In his role as director of UC Riverside’s Center for Invasive Species Research, Hoddle is one of the people best qualified to keep the weevil threat at bay.

Working with insects is something Hoddle has always wanted to do. Growing up in New Zealand, he’d design houses out of toilet paper rolls for giant flightless grasshoppers called weta, and delight in figuring out their favorite foods. Then in college, he read about a lake in Papua New Guinea choking with an invasive water weed. By introducing a weevil that feasts on the weed, scientists eliminated the plant hazard.

“Their work made it so people could use the lake again safely, and it reduced people’s exposure to mosquito-borne diseases. That was mind blowing! And it was a turning point for me,” Hoddle said.

During his undergraduate studies, Hoddle spent five years training in the New Zealand Army Reserves as an engineer. There he learned practical skills, like how to use chainsaws, lay explosives, clear booby traps and mines, lay lines for freshwater supplies, and build floating pontoon bridges.

“These are the skills that now help me trap insects in remote locations around the world,” Hoddle said. “I got used to pushing my way through prickly plants, having to be up to my waist in water, lying in cold mud when it was pouring with rain, tramping around all day digging holes, and looking for stuff with all my gear on. Doing this when looking for bugs isn’t as big a deal for me because of the training I had.”

The hunt for Hoddle’s holy grail — a solution to weevil invasions — has taken him and his entomologist wife Christina to Thailand, Vietnam, Cambodia, the Philippines, Indonesia, and Mexico. Previously, the pair traveled to Pakistan, working for up to three months at a time searching for an enemy of the Asian citrus psyllid, a citrus killer. Psyllid numbers have since been reduced by more than 70% in California because of a highly effective natural enemy they found.

Hoddle’s Ph.D. pedigree and affinity for adventures in rough, foreign terrain have garnered him frequent comparisons to famed, fictional archaeology professor Indiana Jones. The incredible collection of artifacts from a wide variety of cultures in his office at UCR — carved wooden ceremonial masks, insect artwork, an ornate sake bottle — only enhances the sense you’re in an adventurer’s temple.

Fly Fishing Lure

This was a gift from a former student who happened to know that Hoddle is an avid fly fisher. He’s been fishing since he was 12, and still enjoys the hobby when he goes back to New Zealand. He takes his two sons, ages 7 and 11, with him now. Fly fishing uses lures made of feathers that are tied to look like insects that fish feed on. However, this particular lure is for salmon fishing, so it’s not one he’d use for trout fishing in New Zealand’s lakes and rivers. “Salmon lures can get extremely artistic though — you can see there’s an amazing collection of feathers on it,” Hoddle said. “They are works of art, and some of them are extremely valuable.”

Beetle Art

This artwork was a gift from Hoddle’s Ph.D. adviser Roy Van Driesche, professor emeritus of entomology at the University of Massachusetts, Amherst. “Roy liked some of the biological control work I had done in New Zealand,” Hoddle said. “He called me up, asked me if I’d like to do similar work with him. I thought, sure, why not? What an adventure! I quit my job, got out of the army, came to the States, and although unintended, I never left.” Hoddle and Van Driesche developed a successful control program for whiteflies, which attack poinsettias. The program they developed enabled growers to control the pest without having to rely so heavily on insecticides. “After arriving at UCR in 1997, I came to see the image as representing my dual roles here,” he said. “I visualize myself as the goliath beetle in the middle holding off a giant Atlas beetle on one side and a robust Hercules beetle on the other, which are the extension and research components of my responsibilities.”

Ornate Saki Bottle

This was a gift from former student Matt Kamiyama, who worked on brown marmorated stink bugs, which are invasive in California. Native to Asia, stink bugs are serious pests of fruits, vegetables, and other crops. The work Kamiyama did with Hoddle’s group on the stinky invaders helped him return to Japan and secure a doctoral position to work on the biological control of this pest. Hoddle has never opened this bottle. “The wrapping is just so beautiful — I don’t want to ruin it,” Hoddle said.

El Diablo Mask

Hoddle’s lab deals with non-native insect pests that come from other parts of the world, and he often goes overseas to study them in their native ranges. Hoddle has done work on avocados in Mexico, Guatemala, Peru, Ecuador, and Tanzania. This El Diablo mask is from Guatemala, where they were looking for natural enemies of fruit-feeding moths, the “diablos” for avocado growers down there, Hoddle said. “Living and working in Guatemala was a transformative experience for me,” he said. “I learned to speak a modest amount of Spanish. This was a liberating and empowering thing to be able to do and opened so many doors to new friends and collaborative research opportunities.” Hoddle did this work because of concerns about the moths coming back to California and attacking the state’s avocados. “They haven’t, yet. But we wanted to be ahead of the curve,” he said. “I look at this kind of proactive overseas work as an insurance policy. Hope you don’t need it, but if you do, you’ve got it in place and can get on it quickly.”

Return to UCR Magazine: Winter 2024