Miller Moths Invading the Region

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You've probably been battling them ever since the weather turned warm: Miller moths, those giant butterflies of the night that just love the lights on -- and in -- your house. And no, you're not going crazy: There actually are more of them this year.

In neighboring states, the miller's larvae -- the army cutworm -- were unusually abundant this spring, and that's bad news for wheat and alfalfa crops there. But it also means more moths.

University of Wyoming's Assistant Extension Entomologist, Scott Schell, says a wet fall and then a mild spring have made for a good year for miller moths. Right now they're travelling, which means a new swarm is coming your way every night. "It's this spring migration toward the higher elevations as they kind of follow the blooming of the plants up into the mountains," Schell explained.

Adults, luckily, are just a nuisance: they won't eat your clothes or your flour, or lay any eggs -- for now. "As adults, they're feeding on nectar of flowering plants," Schell said. The really good news? You may get a break soon. "I would say we're past the peak, but it might last for another ten days before they won't be such an annoyance," Schell added.

Meanwhile, you can try a few things. Turning lights off can help keep from distracting them from their destination; they get confused you know they're travelling at night and run into artificial light sources. And make sure you seal windows and openings. Once they inevitably do get inside, there are a few destruction techniques.

You've probably heard of the soapy water method: placing a light above a bowl of soapy water. The light gets them going in circles because it distorts their flight path, at some point they fall in, and the soap keeps the water from just sliding off their scaly wings.

The "bug zapper" is effective, but fried moths are a little smelly, and possibly a bit traumatic to watch agonize.

Vacuums will do the job quite nicely if you can reach the moths, just don't forget to empty the filter frequently.

And if the moths are still driving you buggy, maybe we just need to think about how special a creature the Miller really is. For one, they're actually a major food source for the grizzly bear! "They'll spend the day underneath rocks, and the grizzly bears in those areas like around Yellowstone will spend all day flipping rocks and eating miller moths," Schell explained. Eating several hundred of them a day can give the bears quite a bit of nutrition.

"It's kind of remarkable when you think about their role in the ecosystem and how far they're traveling," Schell added: "and they're probably an important pollinator in our alpine regions," noting they live in large numbers up in the mountains during the summer.

The bad news? They'll be making their return migration in the fall, and that's when they'll be laying their eggs.