One Small Arizona City Has A Big Bug Problem

By Casey Kuhn
Published: Thursday, September 22, 2016 - 8:12am
Updated: Thursday, September 22, 2016 - 2:21pm
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(Photo by Casey Kuhn - KJZZ)
Bullhead City Pest Abatement Manager Joe Iburg stands by the Colorado River near the Davis Dam.
(Photo by Casey Kuhn - KJZZ)
Joe Iburg holds up a vial containing mosquitoes he is studying.
(Photo by Casey Kuhn - KJZZ)
An example of how caddisflies invade river-front properties in Bullhead City.
(Photo by Casey Kuhn - KJZZ)
The Spradlings stand on their deck looking out at the Colorado River. They say they can't use their outdoor space in the cooler months because the caddisflies are so bad.

Bullhead City sits on the Colorado River right near the junction of California, Nevada and Arizona and residents take pride in their river-front properties and parks. Those calm days on the river have been disrupted as swarms of insects, called caddisflies, have invaded. The city has invested in an entomologist to study what’s really bugging the locals.


Joe Iburg walked along the Colorado river picking up his low-tech research traps in the early afternoon — they’re sticky yellow rectangles he’s set up in three different locations, each a little farther from the Davis Dam.

At this particular spot on the river, the caddisflies are out in droves — it’s hard to even talk without some flying in your mouth.

“That’s why they needed somebody to come study this,” Iburg said.

Iburg is an entomologist and was recently hired by Bullhead City to study why these bugs have suddenly come to the area.

“Most places in the country where caddisflies become a problem it’s only for a couple weeks. Here they can reach nuisance levels for months out of the year.”

Caddisflies are relatively harmless moth-looking insects about an inch long. They come out in the early fall and stick around in the cooler months.

It’s not the first time Bullhead City has dealt with river bugs. The city has had a tax-funded pest abatement district for 32 years. It was first established to get rid of black flies that plagued locals in 1984.

Iburg is also tasked with controlling mosquitoes in the soccer fields that bring in tournaments — and tourism money — into the area.

He takes me to the fields and we study stagnant little puddles from irrigation that are a perfect breeding ground for mosquitoes. We look for signs of the bug — but don’t find any because he’s already treated the area with a larvacide.

“I won’t have any mosquitoes to show you, which is a good thing, for the city. Hopefully.”

It is a good thing because this type of mosquito is so aggressive it can bite through clothing, and drive soccer players and their families away.

By hiring a bug expert, City Manager Toby Cotter hopes to sidestep any potential loss to tourism.

“It would be devastating to our economy," Cotter said. "So we have to keep our tourism economy strong. Part of that is making sure the environment itself is not impacted.”

Cotter said the economy’s not been affected yet, but with the recent caddisfly issue, local realtors say their business has taken a hit.

“They were showing riverfront homes and the potential buyers were saying, ‘Whoa, are these normal?’” Cotter said about the caddisflies.

Pricey riverfront properties swarmed

Following the river south a ways, you hit Camino del Rio, a street lined with million-dollar homes like the one built by resident Wayne Spradling and his wife Phyllis.

“I find them in the house everywhere, on the floor, on the counter here,” Phyllis said as she gave a tour of her home.

The Spradling’s all-white home on the river is meticulously clean and provides a stark contrast to the dark brown caddisflies all over the windows and doors. Phyllis laments how the pests have hurt the property value and keep her from enjoying the retired life.

“This has been going on for like five, six years," she said. "This is horrible. I feel bad for all of us on the river because our property, we can’t enjoy it. I don’t know how anyone else enjoys it but it’s really bad.”

The Spradling’s have been here for more than 25 years, and are hoping for a bug solution because they plan to stick around.

Pest Abatement Manager Joe Iburg will continue to study the caddisflies to understand why they are just emerging now, and how to control them.

Some current theories are that because there are less trout stocked in the Colorado, the caddisflies have been able to breed out of control. Or it could be connected to more algae growth in certain parts of the river. Whatever the cause, the Spradlings and their neighbors will just have to learn to co-exist with the small, winged creatures.

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